libgo: Update to weekly.2012-02-22 release.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@184819 138bc75d-0d04-0410-961f-82ee72b054a4
author: ian <ian@138bc75d-0d04-0410-961f-82ee72b054a4> 2012-03-02 20:01:37 +0000
committer: ian <ian@138bc75d-0d04-0410-961f-82ee72b054a4> 2012-03-02 20:01:37 +0000
commit: ef10b1dda693467283a3645a5da610e810149764 (patch)
tree: 3eeb8918d39d675108073c8b76d6dd10586a608c /libgo
parent: ea6ad4ae9afbd45b5c19aadab39ddbf1db0d50f8 (diff)
download: gcc-ef10b1dda693467283a3645a5da610e810149764.tar.gz
208 files changed, 5192 insertions, 1993 deletions
diff --git a/libgo/MERGE b/libgo/MERGE
index a760ae9c8de..9605a8a9040 100644
--- a/libgo/MERGE
+++ b/libgo/MERGE
@@ -1,4 +1,4 @@
-43cf9b39b647
+96bd78e7d35e
 
 The first line of this file holds the Mercurial revision number of the
 last merge done from the master library sources.
diff --git a/libgo/Makefile.am b/libgo/Makefile.am
index 1167a3f7ed0..eb764df0eab 100644
--- a/libgo/Makefile.am
+++ b/libgo/Makefile.am
@@ -504,7 +504,7 @@ runtime1.c: $(srcdir)/runtime/runtime1.goc goc2c
 	mv -f $@.tmp $@
 
 sema.c: $(srcdir)/runtime/sema.goc goc2c
-	./goc2c --gcc --go-prefix libgo_runtime $< > $@.tmp
+	./goc2c --gcc --go-prefix libgo_sync $< > $@.tmp
 	mv -f $@.tmp $@
 
 sigqueue.c: $(srcdir)/runtime/sigqueue.goc goc2c
@@ -847,6 +847,7 @@ go_sync_files = \
 	go/sync/cond.go \
 	go/sync/mutex.go \
 	go/sync/once.go \
+	go/sync/runtime.go \
 	go/sync/rwmutex.go \
 	go/sync/waitgroup.go
 
@@ -878,6 +879,7 @@ go_time_files = \
 	go/time/tick.go \
 	go/time/time.go \
 	go/time/zoneinfo.go \
+	go/time/zoneinfo_read.go \
 	go/time/zoneinfo_unix.go
 
 go_unicode_files = \
@@ -1091,6 +1093,7 @@ go_exp_norm_files = \
 	go/exp/norm/composition.go \
 	go/exp/norm/forminfo.go \
 	go/exp/norm/input.go \
+	go/exp/norm/iter.go \
 	go/exp/norm/normalize.go \
 	go/exp/norm/readwriter.go \
 	go/exp/norm/tables.go \
@@ -1132,7 +1135,8 @@ go_go_doc_files = \
 	go/go/doc/example.go \
 	go/go/doc/exports.go \
 	go/go/doc/filter.go \
-	go/go/doc/reader.go
+	go/go/doc/reader.go \
+	go/go/doc/synopsis.go
 go_go_parser_files = \
 	go/go/parser/interface.go \
 	go/go/parser/parser.go
@@ -1159,7 +1163,6 @@ go_hash_fnv_files = \
 
 go_html_template_files = \
 	go/html/template/attr.go \
-	go/html/template/clone.go \
 	go/html/template/content.go \
 	go/html/template/context.go \
 	go/html/template/css.go \
diff --git a/libgo/Makefile.in b/libgo/Makefile.in
index b1d1d4c561e..4604e560c9b 100644
--- a/libgo/Makefile.in
+++ b/libgo/Makefile.in
@@ -1157,6 +1157,7 @@ go_sync_files = \
 	go/sync/cond.go \
 	go/sync/mutex.go \
 	go/sync/once.go \
+	go/sync/runtime.go \
 	go/sync/rwmutex.go \
 	go/sync/waitgroup.go
 
@@ -1182,6 +1183,7 @@ go_time_files = \
 	go/time/tick.go \
 	go/time/time.go \
 	go/time/zoneinfo.go \
+	go/time/zoneinfo_read.go \
 	go/time/zoneinfo_unix.go
 
 go_unicode_files = \
@@ -1427,6 +1429,7 @@ go_exp_norm_files = \
 	go/exp/norm/composition.go \
 	go/exp/norm/forminfo.go \
 	go/exp/norm/input.go \
+	go/exp/norm/iter.go \
 	go/exp/norm/normalize.go \
 	go/exp/norm/readwriter.go \
 	go/exp/norm/tables.go \
@@ -1474,7 +1477,8 @@ go_go_doc_files = \
 	go/go/doc/example.go \
 	go/go/doc/exports.go \
 	go/go/doc/filter.go \
-	go/go/doc/reader.go
+	go/go/doc/reader.go \
+	go/go/doc/synopsis.go
 
 go_go_parser_files = \
 	go/go/parser/interface.go \
@@ -1508,7 +1512,6 @@ go_hash_fnv_files = \
 
 go_html_template_files = \
 	go/html/template/attr.go \
-	go/html/template/clone.go \
 	go/html/template/content.go \
 	go/html/template/context.go \
 	go/html/template/css.go \
@@ -4318,7 +4321,7 @@ runtime1.c: $(srcdir)/runtime/runtime1.goc goc2c
 	mv -f $@.tmp $@
 
 sema.c: $(srcdir)/runtime/sema.goc goc2c
-	./goc2c --gcc --go-prefix libgo_runtime $< > $@.tmp
+	./goc2c --gcc --go-prefix libgo_sync $< > $@.tmp
 	mv -f $@.tmp $@
 
 sigqueue.c: $(srcdir)/runtime/sigqueue.goc goc2c
diff --git a/libgo/go/bufio/bufio.go b/libgo/go/bufio/bufio.go
index 156dddfcf07..6f3b1eec971 100644
--- a/libgo/go/bufio/bufio.go
+++ b/libgo/go/bufio/bufio.go
@@ -106,9 +106,12 @@ func (b *Reader) Peek(n int) ([]byte, error) {
 	if m > n {
 		m = n
 	}
-	err := b.readErr()
-	if m < n && err == nil {
-		err = ErrBufferFull
+	var err error
+	if m < n {
+		err = b.readErr()
+		if err == nil {
+			err = ErrBufferFull
+		}
 	}
 	return b.buf[b.r : b.r+m], err
 }
diff --git a/libgo/go/bufio/bufio_test.go b/libgo/go/bufio/bufio_test.go
index 9aec61ec426..a43cbd23a64 100644
--- a/libgo/go/bufio/bufio_test.go
+++ b/libgo/go/bufio/bufio_test.go
@@ -539,6 +539,27 @@ func TestPeek(t *testing.T) {
 	if _, err := buf.Peek(1); err != io.EOF {
 		t.Fatalf("want EOF got %v", err)
 	}
+
+	// Test for issue 3022, not exposing a reader's error on a successful Peek.
+	buf = NewReaderSize(dataAndEOFReader("abcd"), 32)
+	if s, err := buf.Peek(2); string(s) != "ab" || err != nil {
+		t.Errorf(`Peek(2) on "abcd", EOF = %q, %v; want "ab", nil`, string(s), err)
+	}
+	if s, err := buf.Peek(4); string(s) != "abcd" || err != nil {
+		t.Errorf(`Peek(4) on "abcd", EOF = %q, %v; want "abcd", nil`, string(s), err)
+	}
+	if n, err := buf.Read(p[0:5]); string(p[0:n]) != "abcd" || err != nil {
+		t.Fatalf("Read after peek = %q, %v; want abcd, EOF", p[0:n], err)
+	}
+	if n, err := buf.Read(p[0:1]); string(p[0:n]) != "" || err != io.EOF {
+		t.Fatalf(`second Read after peek = %q, %v; want "", EOF`, p[0:n], err)
+	}
+}
+
+type dataAndEOFReader string
+
+func (r dataAndEOFReader) Read(p []byte) (int, error) {
+	return copy(p, r), io.EOF
 }
 
 func TestPeekThenUnreadRune(t *testing.T) {
diff --git a/libgo/go/bytes/bytes.go b/libgo/go/bytes/bytes.go
index e94a0ec5c4f..7d1426fb417 100644
--- a/libgo/go/bytes/bytes.go
+++ b/libgo/go/bytes/bytes.go
@@ -13,6 +13,7 @@ import (
 
 // Compare returns an integer comparing the two byte arrays lexicographically.
 // The result will be 0 if a==b, -1 if a < b, and +1 if a > b
+// A nil argument is equivalent to an empty slice.
 func Compare(a, b []byte) int {
 	m := len(a)
 	if m > len(b) {
@@ -37,6 +38,7 @@ func Compare(a, b []byte) int {
 }
 
 // Equal returns a boolean reporting whether a == b.
+// A nil argument is equivalent to an empty slice.
 func Equal(a, b []byte) bool
 
 func equalPortable(a, b []byte) bool {
diff --git a/libgo/go/bytes/bytes_test.go b/libgo/go/bytes/bytes_test.go
index 2a1d41b910e..000f235176d 100644
--- a/libgo/go/bytes/bytes_test.go
+++ b/libgo/go/bytes/bytes_test.go
@@ -46,32 +46,39 @@ type BinOpTest struct {
 	i int
 }
 
-var comparetests = []BinOpTest{
-	{"", "", 0},
-	{"a", "", 1},
-	{"", "a", -1},
-	{"abc", "abc", 0},
-	{"ab", "abc", -1},
-	{"abc", "ab", 1},
-	{"x", "ab", 1},
-	{"ab", "x", -1},
-	{"x", "a", 1},
-	{"b", "x", -1},
+var compareTests = []struct {
+	a, b []byte
+	i    int
+}{
+	{[]byte(""), []byte(""), 0},
+	{[]byte("a"), []byte(""), 1},
+	{[]byte(""), []byte("a"), -1},
+	{[]byte("abc"), []byte("abc"), 0},
+	{[]byte("ab"), []byte("abc"), -1},
+	{[]byte("abc"), []byte("ab"), 1},
+	{[]byte("x"), []byte("ab"), 1},
+	{[]byte("ab"), []byte("x"), -1},
+	{[]byte("x"), []byte("a"), 1},
+	{[]byte("b"), []byte("x"), -1},
+	// nil tests
+	{nil, nil, 0},
+	{[]byte(""), nil, 0},
+	{nil, []byte(""), 0},
+	{[]byte("a"), nil, 1},
+	{nil, []byte("a"), -1},
 }
 
 func TestCompare(t *testing.T) {
-	for _, tt := range comparetests {
-		a := []byte(tt.a)
-		b := []byte(tt.b)
-		cmp := Compare(a, b)
+	for _, tt := range compareTests {
+		cmp := Compare(tt.a, tt.b)
 		if cmp != tt.i {
 			t.Errorf(`Compare(%q, %q) = %v`, tt.a, tt.b, cmp)
 		}
-		eql := Equal(a, b)
+		eql := Equal(tt.a, tt.b)
 		if eql != (tt.i == 0) {
 			t.Errorf(`Equal(%q, %q) = %v`, tt.a, tt.b, eql)
 		}
-		eql = EqualPortable(a, b)
+		eql = EqualPortable(tt.a, tt.b)
 		if eql != (tt.i == 0) {
 			t.Errorf(`EqualPortable(%q, %q) = %v`, tt.a, tt.b, eql)
 		}
diff --git a/libgo/go/bytes/example_test.go b/libgo/go/bytes/example_test.go
index 0234a012a4e..6fe8cd5a90c 100644
--- a/libgo/go/bytes/example_test.go
+++ b/libgo/go/bytes/example_test.go
@@ -11,18 +11,18 @@ import (
 	"os"
 )
 
-// Hello world!
 func ExampleBuffer() {
 	var b Buffer // A Buffer needs no initialization.
 	b.Write([]byte("Hello "))
 	b.Write([]byte("world!"))
 	b.WriteTo(os.Stdout)
+	// Output: Hello world!
 }
 
-// Gophers rule!
 func ExampleBuffer_reader() {
 	// A Buffer can turn a string or a []byte into an io.Reader.
 	buf := NewBufferString("R29waGVycyBydWxlIQ==")
 	dec := base64.NewDecoder(base64.StdEncoding, buf)
 	io.Copy(os.Stdout, dec)
+	// Output: Gophers rule!
 }
diff --git a/libgo/go/compress/flate/deflate_test.go b/libgo/go/compress/flate/deflate_test.go
index a76e2d930f6..543c5950586 100644
--- a/libgo/go/compress/flate/deflate_test.go
+++ b/libgo/go/compress/flate/deflate_test.go
@@ -306,6 +306,9 @@ func TestDeflateInflateString(t *testing.T) {
 			t.Error(err)
 		}
 		testToFromWithLimit(t, gold, test.label, test.limit)
+		if testing.Short() {
+			break
+		}
 	}
 }
 
@@ -363,6 +366,10 @@ func TestWriterDict(t *testing.T) {
 
 // See http://code.google.com/p/go/issues/detail?id=2508
 func TestRegression2508(t *testing.T) {
+	if testing.Short() {
+		t.Logf("test disabled with -short")
+		return
+	}
 	w, err := NewWriter(ioutil.Discard, 1)
 	if err != nil {
 		t.Fatalf("NewWriter: %v", err)
diff --git a/libgo/go/container/heap/example_test.go b/libgo/go/container/heap/example_test.go
index c3b8d94cb2a..2050bc83591 100644
--- a/libgo/go/container/heap/example_test.go
+++ b/libgo/go/container/heap/example_test.go
@@ -57,11 +57,26 @@ func (pq *PriorityQueue) Pop() interface{} {
 	return item
 }
 
-// 99:seven 88:five 77:zero 66:nine 55:three 44:two 33:six 22:one 11:four 00:eight
-func ExampleInterface() {
-	// The full code of this example, including the methods that implement
-	// heap.Interface, is in the file src/pkg/container/heap/example_test.go.
+// update is not used by the example but shows how to take the top item from
+// the queue, update its priority and value, and put it back.
+func (pq *PriorityQueue) update(value string, priority int) {
+	item := heap.Pop(pq).(*Item)
+	item.value = value
+	item.priority = priority
+	heap.Push(pq, item)
+}
 
+// changePriority is not used by the example but shows how to change the
+// priority of an arbitrary item.
+func (pq *PriorityQueue) changePriority(item *Item, priority int) {
+	heap.Remove(pq, item.index)
+	item.priority = priority
+	heap.Push(pq, item)
+}
+
+// This example pushes 10 items into a PriorityQueue and takes them out in
+// order of priority.
+func Example() {
 	const nItem = 10
 	// Random priorities for the items (a permutation of 0..9, times 11)).
 	priorities := [nItem]int{
@@ -85,21 +100,6 @@ func ExampleInterface() {
 		item := heap.Pop(&pq).(*Item)
 		fmt.Printf("%.2d:%s ", item.priority, item.value)
 	}
-}
-
-// update is not used by the example but shows how to take the top item from the queue,
-// update its priority and value, and put it back.
-func (pq *PriorityQueue) update(value string, priority int) {
-	item := heap.Pop(pq).(*Item)
-	item.value = value
-	item.priority = priority
-	heap.Push(pq, item)
-}
-
-// changePriority is not used by the example but shows how to change the priority of an arbitrary
-// item.
-func (pq *PriorityQueue) changePriority(item *Item, priority int) {
-	heap.Remove(pq, item.index)
-	item.priority = priority
-	heap.Push(pq, item)
+	// Output:
+	// 99:seven 88:five 77:zero 66:nine 55:three 44:two 33:six 22:one 11:four 00:eight
 }
diff --git a/libgo/go/crypto/dsa/dsa.go b/libgo/go/crypto/dsa/dsa.go
index f7c47831790..05766a2f136 100644
--- a/libgo/go/crypto/dsa/dsa.go
+++ b/libgo/go/crypto/dsa/dsa.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// Package dsa implements the Digital Signature Algorithm, as defined in FIPS 186-3
+// Package dsa implements the Digital Signature Algorithm, as defined in FIPS 186-3.
 package dsa
 
 import (
diff --git a/libgo/go/crypto/md5/md5_test.go b/libgo/go/crypto/md5/md5_test.go
index b15e4668c32..aae875464f9 100644
--- a/libgo/go/crypto/md5/md5_test.go
+++ b/libgo/go/crypto/md5/md5_test.go
@@ -2,9 +2,10 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-package md5
+package md5_test
 
 import (
+	"crypto/md5"
 	"fmt"
 	"io"
 	"testing"
@@ -52,7 +53,7 @@ var golden = []md5Test{
 func TestGolden(t *testing.T) {
 	for i := 0; i < len(golden); i++ {
 		g := golden[i]
-		c := New()
+		c := md5.New()
 		for j := 0; j < 3; j++ {
 			if j < 2 {
 				io.WriteString(c, g.in)
@@ -69,3 +70,11 @@ func TestGolden(t *testing.T) {
 		}
 	}
 }
+
+func ExampleNew() {
+	h := md5.New()
+	io.WriteString(h, "The fog is getting thicker!")
+	io.WriteString(h, "And Leon's getting laaarger!")
+	fmt.Printf("%x", h.Sum(nil))
+	// Output: e2c569be17396eca2a2e3c11578123ed
+}
diff --git a/libgo/go/crypto/sha1/sha1_test.go b/libgo/go/crypto/sha1/sha1_test.go
index c23df6c41e9..2dc14ac9868 100644
--- a/libgo/go/crypto/sha1/sha1_test.go
+++ b/libgo/go/crypto/sha1/sha1_test.go
@@ -4,9 +4,10 @@
 
 // SHA1 hash algorithm.  See RFC 3174.
 
-package sha1
+package sha1_test
 
 import (
+	"crypto/sha1"
 	"fmt"
 	"io"
 	"testing"
@@ -54,7 +55,7 @@ var golden = []sha1Test{
 func TestGolden(t *testing.T) {
 	for i := 0; i < len(golden); i++ {
 		g := golden[i]
-		c := New()
+		c := sha1.New()
 		for j := 0; j < 3; j++ {
 			if j < 2 {
 				io.WriteString(c, g.in)
@@ -71,3 +72,10 @@ func TestGolden(t *testing.T) {
 		}
 	}
 }
+
+func ExampleNew() {
+	h := sha1.New()
+	io.WriteString(h, "His money is twice tainted: 'taint yours and 'taint mine.")
+	fmt.Printf("% x", h.Sum(nil))
+	// Output: 59 7f 6a 54 00 10 f9 4c 15 d7 18 06 a9 9a 2c 87 10 e7 47 bd
+}
diff --git a/libgo/go/crypto/tls/handshake_client.go b/libgo/go/crypto/tls/handshake_client.go
index 687e5ef11b4..0d7b806ff5b 100644
--- a/libgo/go/crypto/tls/handshake_client.go
+++ b/libgo/go/crypto/tls/handshake_client.go
@@ -273,7 +273,7 @@ func (c *Conn) clientHandshake() error {
 	masterSecret, clientMAC, serverMAC, clientKey, serverKey, clientIV, serverIV :=
 		keysFromPreMasterSecret(c.vers, preMasterSecret, hello.random, serverHello.random, suite.macLen, suite.keyLen, suite.ivLen)
 
-	clientCipher := suite.cipher(clientKey, clientIV, false /* not for reading */ )
+	clientCipher := suite.cipher(clientKey, clientIV, false /* not for reading */)
 	clientHash := suite.mac(c.vers, clientMAC)
 	c.out.prepareCipherSpec(c.vers, clientCipher, clientHash)
 	c.writeRecord(recordTypeChangeCipherSpec, []byte{1})
@@ -294,7 +294,7 @@ func (c *Conn) clientHandshake() error {
 	finishedHash.Write(finished.marshal())
 	c.writeRecord(recordTypeHandshake, finished.marshal())
 
-	serverCipher := suite.cipher(serverKey, serverIV, true /* for reading */ )
+	serverCipher := suite.cipher(serverKey, serverIV, true /* for reading */)
 	serverHash := suite.mac(c.vers, serverMAC)
 	c.in.prepareCipherSpec(c.vers, serverCipher, serverHash)
 	c.readRecord(recordTypeChangeCipherSpec)
diff --git a/libgo/go/crypto/tls/handshake_server.go b/libgo/go/crypto/tls/handshake_server.go
index fb53767f3e0..23ec5587235 100644
--- a/libgo/go/crypto/tls/handshake_server.go
+++ b/libgo/go/crypto/tls/handshake_server.go
@@ -295,7 +295,7 @@ FindCipherSuite:
 	masterSecret, clientMAC, serverMAC, clientKey, serverKey, clientIV, serverIV :=
 		keysFromPreMasterSecret(c.vers, preMasterSecret, clientHello.random, hello.random, suite.macLen, suite.keyLen, suite.ivLen)
 
-	clientCipher := suite.cipher(clientKey, clientIV, true /* for reading */ )
+	clientCipher := suite.cipher(clientKey, clientIV, true /* for reading */)
 	clientHash := suite.mac(c.vers, clientMAC)
 	c.in.prepareCipherSpec(c.vers, clientCipher, clientHash)
 	c.readRecord(recordTypeChangeCipherSpec)
@@ -333,7 +333,7 @@ FindCipherSuite:
 
 	finishedHash.Write(clientFinished.marshal())
 
-	serverCipher := suite.cipher(serverKey, serverIV, false /* not for reading */ )
+	serverCipher := suite.cipher(serverKey, serverIV, false /* not for reading */)
 	serverHash := suite.mac(c.vers, serverMAC)
 	c.out.prepareCipherSpec(c.vers, serverCipher, serverHash)
 	c.writeRecord(recordTypeChangeCipherSpec, []byte{1})
diff --git a/libgo/go/database/sql/convert.go b/libgo/go/database/sql/convert.go
index 4afa2bef753..bfcb03ccf8d 100644
--- a/libgo/go/database/sql/convert.go
+++ b/libgo/go/database/sql/convert.go
@@ -17,8 +17,8 @@ import (
 // subsetTypeArgs takes a slice of arguments from callers of the sql
 // package and converts them into a slice of the driver package's
 // "subset types".
-func subsetTypeArgs(args []interface{}) ([]interface{}, error) {
-	out := make([]interface{}, len(args))
+func subsetTypeArgs(args []interface{}) ([]driver.Value, error) {
+	out := make([]driver.Value, len(args))
 	for n, arg := range args {
 		var err error
 		out[n], err = driver.DefaultParameterConverter.ConvertValue(arg)
diff --git a/libgo/go/database/sql/driver/driver.go b/libgo/go/database/sql/driver/driver.go
index b9300776050..7f986b80f2c 100644
--- a/libgo/go/database/sql/driver/driver.go
+++ b/libgo/go/database/sql/driver/driver.go
@@ -6,21 +6,20 @@
 // drivers as used by package sql.
 //
 // Most code should use package sql.
-//
-// Drivers only need to be aware of a subset of Go's types.  The sql package
-// will convert all types into one of the following:
+package driver
+
+import "errors"
+
+// A driver Value is a value that drivers must be able to handle.
+// A Value is either nil or an instance of one of these types:
 //
 //   int64
 //   float64
 //   bool
-//   nil
 //   []byte
 //   string   [*] everywhere except from Rows.Next.
 //   time.Time
-//
-package driver
-
-import "errors"
+type Value interface{}
 
 // Driver is the interface that must be implemented by a database
 // driver.
@@ -50,11 +49,9 @@ var ErrSkip = errors.New("driver: skip fast-path; continue as if unimplemented")
 // first prepare a query, execute the statement, and then close the
 // statement.
 //
-// All arguments are of a subset type as defined in the package docs.
-//
 // Exec may return ErrSkip.
 type Execer interface {
-	Exec(query string, args []interface{}) (Result, error)
+	Exec(query string, args []Value) (Result, error)
 }
 
 // Conn is a connection to a database. It is not used concurrently
@@ -127,18 +124,17 @@ type Stmt interface {
 	NumInput() int
 
 	// Exec executes a query that doesn't return rows, such
-	// as an INSERT or UPDATE.  The args are all of a subset
-	// type as defined above.
-	Exec(args []interface{}) (Result, error)
+	// as an INSERT or UPDATE.
+	Exec(args []Value) (Result, error)
 
 	// Exec executes a query that may return rows, such as a
-	// SELECT.  The args of all of a subset type as defined above.
-	Query(args []interface{}) (Rows, error)
+	// SELECT.
+	Query(args []Value) (Rows, error)
 }
 
 // ColumnConverter may be optionally implemented by Stmt if the
 // the statement is aware of its own columns' types and can
-// convert from any type to a driver subset type.
+// convert from any type to a driver Value.
 type ColumnConverter interface {
 	// ColumnConverter returns a ValueConverter for the provided
 	// column index.  If the type of a specific column isn't known
@@ -162,12 +158,12 @@ type Rows interface {
 	// the provided slice. The provided slice will be the same
 	// size as the Columns() are wide.
 	//
-	// The dest slice may be populated with only with values
-	// of subset types defined above, but excluding string.
+	// The dest slice may be populated only with
+	// a driver Value type, but excluding string.
 	// All string values must be converted to []byte.
 	//
 	// Next should return io.EOF when there are no more rows.
-	Next(dest []interface{}) error
+	Next(dest []Value) error
 }
 
 // Tx is a transaction.
@@ -190,18 +186,19 @@ func (v RowsAffected) RowsAffected() (int64, error) {
 	return int64(v), nil
 }
 
-// DDLSuccess is a pre-defined Result for drivers to return when a DDL
-// command succeeds.
-var DDLSuccess ddlSuccess
+// ResultNoRows is a pre-defined Result for drivers to return when a DDL
+// command (such as a CREATE TABLE) succeeds. It returns an error for both
+// LastInsertId and RowsAffected.
+var ResultNoRows noRows
 
-type ddlSuccess struct{}
+type noRows struct{}
 
-var _ Result = ddlSuccess{}
+var _ Result = noRows{}
 
-func (ddlSuccess) LastInsertId() (int64, error) {
+func (noRows) LastInsertId() (int64, error) {
 	return 0, errors.New("no LastInsertId available after DDL statement")
 }
 
-func (ddlSuccess) RowsAffected() (int64, error) {
+func (noRows) RowsAffected() (int64, error) {
 	return 0, errors.New("no RowsAffected available after DDL statement")
 }
diff --git a/libgo/go/database/sql/driver/types.go b/libgo/go/database/sql/driver/types.go
index ce3c943ead2..3305354dfd0 100644
--- a/libgo/go/database/sql/driver/types.go
+++ b/libgo/go/database/sql/driver/types.go
@@ -17,28 +17,28 @@ import (
 // driver package to provide consistent implementations of conversions
 // between drivers.  The ValueConverters have several uses:
 //
-//  * converting from the subset types as provided by the sql package
+//  * converting from the Value types as provided by the sql package
 //    into a database table's specific column type and making sure it
 //    fits, such as making sure a particular int64 fits in a
 //    table's uint16 column.
 //
 //  * converting a value as given from the database into one of the
-//    subset types.
+//    driver Value types.
 //
-//  * by the sql package, for converting from a driver's subset type
+//  * by the sql package, for converting from a driver's Value type
 //    to a user's type in a scan.
 type ValueConverter interface {
-	// ConvertValue converts a value to a restricted subset type.
-	ConvertValue(v interface{}) (interface{}, error)
+	// ConvertValue converts a value to a driver Value.
+	ConvertValue(v interface{}) (Value, error)
 }
 
-// SubsetValuer is the interface providing the SubsetValue method.
+// Valuer is the interface providing the Value method.
 //
-// Types implementing SubsetValuer interface are able to convert
-// themselves to one of the driver's allowed subset values.
-type SubsetValuer interface {
-	// SubsetValue returns a driver parameter subset value.
-	SubsetValue() (interface{}, error)
+// Types implementing Valuer interface are able to convert
+// themselves to a driver Value.
+type Valuer interface {
+	// Value returns a driver Value.
+	Value() (Value, error)
 }
 
 // Bool is a ValueConverter that converts input values to bools.
@@ -59,7 +59,7 @@ var _ ValueConverter = boolType{}
 
 func (boolType) String() string { return "Bool" }
 
-func (boolType) ConvertValue(src interface{}) (interface{}, error) {
+func (boolType) ConvertValue(src interface{}) (Value, error) {
 	switch s := src.(type) {
 	case bool:
 		return s, nil
@@ -104,7 +104,7 @@ type int32Type struct{}
 
 var _ ValueConverter = int32Type{}
 
-func (int32Type) ConvertValue(v interface{}) (interface{}, error) {
+func (int32Type) ConvertValue(v interface{}) (Value, error) {
 	rv := reflect.ValueOf(v)
 	switch rv.Kind() {
 	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
@@ -137,7 +137,7 @@ var String stringType
 
 type stringType struct{}
 
-func (stringType) ConvertValue(v interface{}) (interface{}, error) {
+func (stringType) ConvertValue(v interface{}) (Value, error) {
 	switch v.(type) {
 	case string, []byte:
 		return v, nil
@@ -151,7 +151,7 @@ type Null struct {
 	Converter ValueConverter
 }
 
-func (n Null) ConvertValue(v interface{}) (interface{}, error) {
+func (n Null) ConvertValue(v interface{}) (Value, error) {
 	if v == nil {
 		return nil, nil
 	}
@@ -164,28 +164,17 @@ type NotNull struct {
 	Converter ValueConverter
 }
 
-func (n NotNull) ConvertValue(v interface{}) (interface{}, error) {
+func (n NotNull) ConvertValue(v interface{}) (Value, error) {
 	if v == nil {
 		return nil, fmt.Errorf("nil value not allowed")
 	}
 	return n.Converter.ConvertValue(v)
 }
 
-// IsParameterSubsetType reports whether v is of a valid type for a
-// parameter. These types are:
-//
-//   int64
-//   float64
-//   bool
-//   nil
-//   []byte
-//   time.Time
-//   string
-//
-// This is the same list as IsScanSubsetType, with the addition of
-// string.
-func IsParameterSubsetType(v interface{}) bool {
-	if IsScanSubsetType(v) {
+// IsValue reports whether v is a valid Value parameter type.
+// Unlike IsScanValue, IsValue permits the string type.
+func IsValue(v interface{}) bool {
+	if IsScanValue(v) {
 		return true
 	}
 	if _, ok := v.(string); ok {
@@ -194,18 +183,9 @@ func IsParameterSubsetType(v interface{}) bool {
 	return false
 }
 
-// IsScanSubsetType reports whether v is of a valid type for a
-// value populated by Rows.Next. These types are:
-//
-//   int64
-//   float64
-//   bool
-//   nil
-//   []byte
-//   time.Time
-//
-// This is the same list as IsParameterSubsetType, without string.
-func IsScanSubsetType(v interface{}) bool {
+// IsScanValue reports whether v is a valid Value scan type.
+// Unlike IsValue, IsScanValue does not permit the string type.
+func IsScanValue(v interface{}) bool {
 	if v == nil {
 		return true
 	}
@@ -221,7 +201,7 @@ func IsScanSubsetType(v interface{}) bool {
 // ColumnConverter.
 //
 // DefaultParameterConverter returns the given value directly if
-// IsSubsetType(value).  Otherwise integer type are converted to
+// IsValue(value).  Otherwise integer type are converted to
 // int64, floats to float64, and strings to []byte.  Other types are
 // an error.
 var DefaultParameterConverter defaultConverter
@@ -230,18 +210,18 @@ type defaultConverter struct{}
 
 var _ ValueConverter = defaultConverter{}
 
-func (defaultConverter) ConvertValue(v interface{}) (interface{}, error) {
-	if IsParameterSubsetType(v) {
+func (defaultConverter) ConvertValue(v interface{}) (Value, error) {
+	if IsValue(v) {
 		return v, nil
 	}
 
-	if svi, ok := v.(SubsetValuer); ok {
-		sv, err := svi.SubsetValue()
+	if svi, ok := v.(Valuer); ok {
+		sv, err := svi.Value()
 		if err != nil {
 			return nil, err
 		}
-		if !IsParameterSubsetType(sv) {
-			return nil, fmt.Errorf("non-subset type %T returned from SubsetValue", sv)
+		if !IsValue(sv) {
+			return nil, fmt.Errorf("non-Value type %T returned from Value", sv)
 		}
 		return sv, nil
 	}
diff --git a/libgo/go/database/sql/fakedb_test.go b/libgo/go/database/sql/fakedb_test.go
index 889e2a25232..fc63f03740a 100644
--- a/libgo/go/database/sql/fakedb_test.go
+++ b/libgo/go/database/sql/fakedb_test.go
@@ -217,7 +217,7 @@ func (c *fakeConn) Close() error {
 	return nil
 }
 
-func checkSubsetTypes(args []interface{}) error {
+func checkSubsetTypes(args []driver.Value) error {
 	for n, arg := range args {
 		switch arg.(type) {
 		case int64, float64, bool, nil, []byte, string, time.Time:
@@ -228,7 +228,7 @@ func checkSubsetTypes(args []interface{}) error {
 	return nil
 }
 
-func (c *fakeConn) Exec(query string, args []interface{}) (driver.Result, error) {
+func (c *fakeConn) Exec(query string, args []driver.Value) (driver.Result, error) {
 	// This is an optional interface, but it's implemented here
 	// just to check that all the args of of the proper types.
 	// ErrSkip is returned so the caller acts as if we didn't
@@ -379,7 +379,7 @@ func (s *fakeStmt) Close() error {
 
 var errClosed = errors.New("fakedb: statement has been closed")
 
-func (s *fakeStmt) Exec(args []interface{}) (driver.Result, error) {
+func (s *fakeStmt) Exec(args []driver.Value) (driver.Result, error) {
 	if s.closed {
 		return nil, errClosed
 	}
@@ -392,12 +392,12 @@ func (s *fakeStmt) Exec(args []interface{}) (driver.Result, error) {
 	switch s.cmd {
 	case "WIPE":
 		db.wipe()
-		return driver.DDLSuccess, nil
+		return driver.ResultNoRows, nil
 	case "CREATE":
 		if err := db.createTable(s.table, s.colName, s.colType); err != nil {
 			return nil, err
 		}
-		return driver.DDLSuccess, nil
+		return driver.ResultNoRows, nil
 	case "INSERT":
 		return s.execInsert(args)
 	}
@@ -405,7 +405,7 @@ func (s *fakeStmt) Exec(args []interface{}) (driver.Result, error) {
 	return nil, fmt.Errorf("unimplemented statement Exec command type of %q", s.cmd)
 }
 
-func (s *fakeStmt) execInsert(args []interface{}) (driver.Result, error) {
+func (s *fakeStmt) execInsert(args []driver.Value) (driver.Result, error) {
 	db := s.c.db
 	if len(args) != s.placeholders {
 		panic("error in pkg db; should only get here if size is correct")
@@ -441,7 +441,7 @@ func (s *fakeStmt) execInsert(args []interface{}) (driver.Result, error) {
 	return driver.RowsAffected(1), nil
 }
 
-func (s *fakeStmt) Query(args []interface{}) (driver.Rows, error) {
+func (s *fakeStmt) Query(args []driver.Value) (driver.Rows, error) {
 	if s.closed {
 		return nil, errClosed
 	}
@@ -548,7 +548,7 @@ func (rc *rowsCursor) Columns() []string {
 	return rc.cols
 }
 
-func (rc *rowsCursor) Next(dest []interface{}) error {
+func (rc *rowsCursor) Next(dest []driver.Value) error {
 	if rc.closed {
 		return errors.New("fakedb: cursor is closed")
 	}
diff --git a/libgo/go/database/sql/sql.go b/libgo/go/database/sql/sql.go
index f14a98c3cf2..62b551d89b5 100644
--- a/libgo/go/database/sql/sql.go
+++ b/libgo/go/database/sql/sql.go
@@ -62,8 +62,8 @@ func (ns *NullString) Scan(value interface{}) error {
 	return convertAssign(&ns.String, value)
 }
 
-// SubsetValue implements the driver SubsetValuer interface.
-func (ns NullString) SubsetValue() (interface{}, error) {
+// Value implements the driver Valuer interface.
+func (ns NullString) Value() (driver.Value, error) {
 	if !ns.Valid {
 		return nil, nil
 	}
@@ -88,8 +88,8 @@ func (n *NullInt64) Scan(value interface{}) error {
 	return convertAssign(&n.Int64, value)
 }
 
-// SubsetValue implements the driver SubsetValuer interface.
-func (n NullInt64) SubsetValue() (interface{}, error) {
+// Value implements the driver Valuer interface.
+func (n NullInt64) Value() (driver.Value, error) {
 	if !n.Valid {
 		return nil, nil
 	}
@@ -114,8 +114,8 @@ func (n *NullFloat64) Scan(value interface{}) error {
 	return convertAssign(&n.Float64, value)
 }
 
-// SubsetValue implements the driver SubsetValuer interface.
-func (n NullFloat64) SubsetValue() (interface{}, error) {
+// Value implements the driver Valuer interface.
+func (n NullFloat64) Value() (driver.Value, error) {
 	if !n.Valid {
 		return nil, nil
 	}
@@ -140,8 +140,8 @@ func (n *NullBool) Scan(value interface{}) error {
 	return convertAssign(&n.Bool, value)
 }
 
-// SubsetValue implements the driver SubsetValuer interface.
-func (n NullBool) SubsetValue() (interface{}, error) {
+// Value implements the driver Valuer interface.
+func (n NullBool) Value() (driver.Value, error) {
 	if !n.Valid {
 		return nil, nil
 	}
@@ -523,8 +523,13 @@ func (tx *Tx) Exec(query string, args ...interface{}) (Result, error) {
 	}
 	defer tx.releaseConn()
 
+	sargs, err := subsetTypeArgs(args)
+	if err != nil {
+		return nil, err
+	}
+
 	if execer, ok := ci.(driver.Execer); ok {
-		resi, err := execer.Exec(query, args)
+		resi, err := execer.Exec(query, sargs)
 		if err == nil {
 			return result{resi}, nil
 		}
@@ -539,11 +544,6 @@ func (tx *Tx) Exec(query string, args ...interface{}) (Result, error) {
 	}
 	defer sti.Close()
 
-	sargs, err := subsetTypeArgs(args)
-	if err != nil {
-		return nil, err
-	}
-
 	resi, err := sti.Exec(sargs)
 	if err != nil {
 		return nil, err
@@ -618,19 +618,21 @@ func (s *Stmt) Exec(args ...interface{}) (Result, error) {
 		return nil, fmt.Errorf("sql: expected %d arguments, got %d", want, len(args))
 	}
 
+	sargs := make([]driver.Value, len(args))
+
 	// Convert args to subset types.
 	if cc, ok := si.(driver.ColumnConverter); ok {
 		for n, arg := range args {
 			// First, see if the value itself knows how to convert
 			// itself to a driver type.  For example, a NullString
 			// struct changing into a string or nil.
-			if svi, ok := arg.(driver.SubsetValuer); ok {
-				sv, err := svi.SubsetValue()
+			if svi, ok := arg.(driver.Valuer); ok {
+				sv, err := svi.Value()
 				if err != nil {
-					return nil, fmt.Errorf("sql: argument index %d from SubsetValue: %v", n, err)
+					return nil, fmt.Errorf("sql: argument index %d from Value: %v", n, err)
 				}
-				if !driver.IsParameterSubsetType(sv) {
-					return nil, fmt.Errorf("sql: argument index %d: non-subset type %T returned from SubsetValue", n, sv)
+				if !driver.IsValue(sv) {
+					return nil, fmt.Errorf("sql: argument index %d: non-subset type %T returned from Value", n, sv)
 				}
 				arg = sv
 			}
@@ -642,25 +644,25 @@ func (s *Stmt) Exec(args ...interface{}) (Result, error) {
 			// truncated), or that a nil can't go into a NOT NULL
 			// column before going across the network to get the
 			// same error.
-			args[n], err = cc.ColumnConverter(n).ConvertValue(arg)
+			sargs[n], err = cc.ColumnConverter(n).ConvertValue(arg)
 			if err != nil {
 				return nil, fmt.Errorf("sql: converting Exec argument #%d's type: %v", n, err)
 			}
-			if !driver.IsParameterSubsetType(args[n]) {
+			if !driver.IsValue(sargs[n]) {
 				return nil, fmt.Errorf("sql: driver ColumnConverter error converted %T to unsupported type %T",
-					arg, args[n])
+					arg, sargs[n])
 			}
 		}
 	} else {
 		for n, arg := range args {
-			args[n], err = driver.DefaultParameterConverter.ConvertValue(arg)
+			sargs[n], err = driver.DefaultParameterConverter.ConvertValue(arg)
 			if err != nil {
 				return nil, fmt.Errorf("sql: converting Exec argument #%d's type: %v", n, err)
 			}
 		}
 	}
 
-	resi, err := si.Exec(args)
+	resi, err := si.Exec(sargs)
 	if err != nil {
 		return nil, err
 	}
@@ -829,7 +831,7 @@ type Rows struct {
 	rowsi       driver.Rows
 
 	closed    bool
-	lastcols  []interface{}
+	lastcols  []driver.Value
 	lasterr   error
 	closeStmt *Stmt // if non-nil, statement to Close on close
 }
@@ -846,7 +848,7 @@ func (rs *Rows) Next() bool {
 		return false
 	}
 	if rs.lastcols == nil {
-		rs.lastcols = make([]interface{}, len(rs.rowsi.Columns()))
+		rs.lastcols = make([]driver.Value, len(rs.rowsi.Columns()))
 	}
 	rs.lasterr = rs.rowsi.Next(rs.lastcols)
 	if rs.lasterr == io.EOF {
diff --git a/libgo/go/debug/dwarf/open.go b/libgo/go/debug/dwarf/open.go
index 9543297e189..37a518b6d37 100644
--- a/libgo/go/debug/dwarf/open.go
+++ b/libgo/go/debug/dwarf/open.go
@@ -31,8 +31,9 @@ type Data struct {
 }
 
 // New returns a new Data object initialized from the given parameters.
-// Clients should typically use [TODO(rsc): method to be named later] instead of calling
-// New directly.
+// Rather than calling this function directly, clients should typically use
+// the DWARF method of the File type of the appropriate package debug/elf,
+// debug/macho, or debug/pe.
 //
 // The []byte arguments are the data from the corresponding debug section
 // in the object file; for example, for an ELF object, abbrev is the contents of
diff --git a/libgo/go/debug/dwarf/testdata/typedef.c b/libgo/go/debug/dwarf/testdata/typedef.c
index 664d021ced5..f05f01564ff 100644
--- a/libgo/go/debug/dwarf/testdata/typedef.c
+++ b/libgo/go/debug/dwarf/testdata/typedef.c
@@ -28,8 +28,13 @@ typedef struct my_struct {
 	volatile int vi;
 	char x : 1;
 	int y : 4;
+	int z[0];
 	long long array[40];
+	int zz[0];
 } t_my_struct;
+typedef struct my_struct1 {
+	int zz [1];
+} t_my_struct1;
 typedef union my_union {
 	volatile int vi;
 	char x : 1;
@@ -65,7 +70,8 @@ t_func_void_of_char *a9;
 t_func_void_of_void *a10;
 t_func_void_of_ptr_char_dots *a11;
 t_my_struct *a12;
-t_my_union *a12a;
+t_my_struct1 *a12a;
+t_my_union *a12b;
 t_my_enum *a13;
 t_my_list *a14;
 t_my_tree *a15;
diff --git a/libgo/go/debug/dwarf/testdata/typedef.elf b/libgo/go/debug/dwarf/testdata/typedef.elf
index 44df8da9bc7..b2062d2c4bb 100755
--- a/libgo/go/debug/dwarf/testdata/typedef.elf
+++ b/libgo/go/debug/dwarf/testdata/typedef.elf
diff --git a/libgo/go/debug/dwarf/testdata/typedef.macho b/libgo/go/debug/dwarf/testdata/typedef.macho
index 41019c1e146..f75afcccbfc 100644
--- a/libgo/go/debug/dwarf/testdata/typedef.macho
+++ b/libgo/go/debug/dwarf/testdata/typedef.macho
diff --git a/libgo/go/debug/dwarf/type.go b/libgo/go/debug/dwarf/type.go
index 9be66658fe9..4502355022d 100644
--- a/libgo/go/debug/dwarf/type.go
+++ b/libgo/go/debug/dwarf/type.go
@@ -426,6 +426,8 @@ func (d *Data) Type(off Offset) (Type, error) {
 		t.StructName, _ = e.Val(AttrName).(string)
 		t.Incomplete = e.Val(AttrDeclaration) != nil
 		t.Field = make([]*StructField, 0, 8)
+		var lastFieldType Type
+		var lastFieldBitOffset int64
 		for kid := next(); kid != nil; kid = next() {
 			if kid.Tag == TagMember {
 				f := new(StructField)
@@ -444,11 +446,32 @@ func (d *Data) Type(off Offset) (Type, error) {
 						goto Error
 					}
 				}
+
+				haveBitOffset := false
 				f.Name, _ = kid.Val(AttrName).(string)
 				f.ByteSize, _ = kid.Val(AttrByteSize).(int64)
-				f.BitOffset, _ = kid.Val(AttrBitOffset).(int64)
+				f.BitOffset, haveBitOffset = kid.Val(AttrBitOffset).(int64)
 				f.BitSize, _ = kid.Val(AttrBitSize).(int64)
 				t.Field = append(t.Field, f)
+
+				bito := f.BitOffset
+				if !haveBitOffset {
+					bito = f.ByteOffset * 8
+				}
+				if bito == lastFieldBitOffset && t.Kind != "union" {
+					// Last field was zero width.  Fix array length.
+					// (DWARF writes out 0-length arrays as if they were 1-length arrays.)
+					zeroArray(lastFieldType)
+				}
+				lastFieldType = f.Type
+				lastFieldBitOffset = bito
+			}
+		}
+		if t.Kind != "union" {
+			b, ok := e.Val(AttrByteSize).(int64)
+			if ok && b*8 == lastFieldBitOffset {
+				// Final field must be zero width.  Fix array length.
+				zeroArray(lastFieldType)
 			}
 		}
 
@@ -579,3 +602,14 @@ Error:
 	delete(d.typeCache, off)
 	return nil, err
 }
+
+func zeroArray(t Type) {
+	for {
+		at, ok := t.(*ArrayType)
+		if !ok {
+			break
+		}
+		at.Count = 0
+		t = at.Type
+	}
+}
diff --git a/libgo/go/debug/dwarf/type_test.go b/libgo/go/debug/dwarf/type_test.go
index b9470a4fcb4..b5b255f6f4a 100644
--- a/libgo/go/debug/dwarf/type_test.go
+++ b/libgo/go/debug/dwarf/type_test.go
@@ -25,13 +25,22 @@ var typedefTests = map[string]string{
 	"t_func_void_of_char":                   "func(char) void",
 	"t_func_void_of_void":                   "func() void",
 	"t_func_void_of_ptr_char_dots":          "func(*char, ...) void",
-	"t_my_struct":                           "struct my_struct {vi volatile int@0; x char@4 : 1@7; y int@4 : 4@27; array [40]long long int@8}",
+	"t_my_struct":                           "struct my_struct {vi volatile int@0; x char@4 : 1@7; y int@4 : 4@27; z [0]int@8; array [40]long long int@8; zz [0]int@328}",
+	"t_my_struct1":                          "struct my_struct1 {zz [1]int@0}",
 	"t_my_union":                            "union my_union {vi volatile int@0; x char@0 : 1@7; y int@0 : 4@28; array [40]long long int@0}",
 	"t_my_enum":                             "enum my_enum {e1=1; e2=2; e3=-5; e4=1000000000000000}",
 	"t_my_list":                             "struct list {val short int@0; next *t_my_list@8}",
 	"t_my_tree":                             "struct tree {left *struct tree@0; right *struct tree@8; val long long unsigned int@16}",
 }
 
+// As Apple converts gcc to a clang-based front end
+// they keep breaking the DWARF output.  This map lists the
+// conversion from real answer to Apple answer.
+var machoBug = map[string]string{
+	"func(*char, ...) void":                                 "func(*char) void",
+	"enum my_enum {e1=1; e2=2; e3=-5; e4=1000000000000000}": "enum my_enum {e1=1; e2=2; e3=-5; e4=-1530494976}",
+}
+
 func elfData(t *testing.T, name string) *Data {
 	f, err := elf.Open(name)
 	if err != nil {
@@ -58,13 +67,13 @@ func machoData(t *testing.T, name string) *Data {
 	return d
 }
 
-func TestTypedefsELF(t *testing.T) { testTypedefs(t, elfData(t, "testdata/typedef.elf")) }
+func TestTypedefsELF(t *testing.T) { testTypedefs(t, elfData(t, "testdata/typedef.elf"), "elf") }
 
 func TestTypedefsMachO(t *testing.T) {
-	testTypedefs(t, machoData(t, "testdata/typedef.macho"))
+	testTypedefs(t, machoData(t, "testdata/typedef.macho"), "macho")
 }
 
-func testTypedefs(t *testing.T, d *Data) {
+func testTypedefs(t *testing.T, d *Data, kind string) {
 	r := d.Reader()
 	seen := make(map[string]bool)
 	for {
@@ -93,7 +102,7 @@ func testTypedefs(t *testing.T, d *Data) {
 					t.Errorf("multiple definitions for %s", t1.Name)
 				}
 				seen[t1.Name] = true
-				if typstr != want {
+				if typstr != want && (kind != "macho" || typstr != machoBug[want]) {
 					t.Errorf("%s:\n\thave %s\n\twant %s", t1.Name, typstr, want)
 				}
 			}
diff --git a/libgo/go/debug/gosym/pclntab_test.go b/libgo/go/debug/gosym/pclntab_test.go
index b90181bdc64..b2400bb3ba7 100644
--- a/libgo/go/debug/gosym/pclntab_test.go
+++ b/libgo/go/debug/gosym/pclntab_test.go
@@ -6,15 +6,37 @@ package gosym
 
 import (
 	"debug/elf"
+	"fmt"
 	"os"
+	"os/exec"
 	"runtime"
+	"strings"
 	"testing"
 )
 
+var pclinetestBinary string
+
 func dotest() bool {
 	// For now, only works on ELF platforms.
-	// TODO: convert to work with new go tool
-	return false && runtime.GOOS == "linux" && runtime.GOARCH == "amd64"
+	if runtime.GOOS != "linux" || runtime.GOARCH != "amd64" {
+		return false
+	}
+	if pclinetestBinary != "" {
+		return true
+	}
+	// This command builds pclinetest from pclinetest.asm;
+	// the resulting binary looks like it was built from pclinetest.s,
+	// but we have renamed it to keep it away from the go tool.
+	pclinetestBinary = os.TempDir() + "/pclinetest"
+	command := fmt.Sprintf("go tool 6a -o %s.6 pclinetest.asm && go tool 6l -E main -o %s %s.6",
+		pclinetestBinary, pclinetestBinary, pclinetestBinary)
+	cmd := exec.Command("sh", "-c", command)
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+	if err := cmd.Run(); err != nil {
+		panic(err)
+	}
+	return true
 }
 
 func getTable(t *testing.T) *Table {
@@ -149,7 +171,7 @@ func TestPCLine(t *testing.T) {
 		return
 	}
 
-	f, tab := crack("_test/pclinetest", t)
+	f, tab := crack(pclinetestBinary, t)
 	text := f.Section(".text")
 	textdat, err := text.Data()
 	if err != nil {
@@ -163,10 +185,13 @@ func TestPCLine(t *testing.T) {
 		file, line, fn := tab.PCToLine(pc)
 		off := pc - text.Addr // TODO(rsc): should not need off; bug in 8g
 		wantLine += int(textdat[off])
+		t.Logf("off is %d", off)
 		if fn == nil {
 			t.Errorf("failed to get line of PC %#x", pc)
-		} else if len(file) < 12 || file[len(file)-12:] != "pclinetest.s" || line != wantLine || fn != sym {
-			t.Errorf("expected %s:%d (%s) at PC %#x, got %s:%d (%s)", "pclinetest.s", wantLine, sym.Name, pc, file, line, fn.Name)
+		} else if !strings.HasSuffix(file, "pclinetest.asm") {
+			t.Errorf("expected %s (%s) at PC %#x, got %s (%s)", "pclinetest.asm", sym.Name, pc, file, fn.Name)
+		} else if line != wantLine || fn != sym {
+			t.Errorf("expected :%d (%s) at PC %#x, got :%d (%s)", wantLine, sym.Name, pc, line, fn.Name)
 		}
 	}
 
diff --git a/libgo/go/encoding/gob/decode.go b/libgo/go/encoding/gob/decode.go
index 750d623cde2..a0bb985300f 100644
--- a/libgo/go/encoding/gob/decode.go
+++ b/libgo/go/encoding/gob/decode.go
@@ -464,7 +464,7 @@ func allocate(rtyp reflect.Type, p uintptr, indir int) uintptr {
 // decodeSingle decodes a top-level value that is not a struct and stores it through p.
 // Such values are preceded by a zero, making them have the memory layout of a
 // struct field (although with an illegal field number).
-func (dec *Decoder) decodeSingle(engine *decEngine, ut *userTypeInfo, basep uintptr) (err error) {
+func (dec *Decoder) decodeSingle(engine *decEngine, ut *userTypeInfo, basep uintptr) {
 	state := dec.newDecoderState(&dec.buf)
 	state.fieldnum = singletonField
 	delta := int(state.decodeUint())
@@ -473,7 +473,7 @@ func (dec *Decoder) decodeSingle(engine *decEngine, ut *userTypeInfo, basep uint
 	}
 	instr := &engine.instr[singletonField]
 	if instr.indir != ut.indir {
-		return errors.New("gob: internal error: inconsistent indirection")
+		errorf("internal error: inconsistent indirection instr %d ut %d", instr.indir, ut.indir)
 	}
 	ptr := unsafe.Pointer(basep) // offset will be zero
 	if instr.indir > 1 {
@@ -481,10 +481,9 @@ func (dec *Decoder) decodeSingle(engine *decEngine, ut *userTypeInfo, basep uint
 	}
 	instr.op(instr, state, ptr)
 	dec.freeDecoderState(state)
-	return nil
 }
 
-// decodeSingle decodes a top-level struct and stores it through p.
+// decodeStruct decodes a top-level struct and stores it through p.
 // Indir is for the value, not the type.  At the time of the call it may
 // differ from ut.indir, which was computed when the engine was built.
 // This state cannot arise for decodeSingle, which is called directly
@@ -839,11 +838,10 @@ func (dec *Decoder) decOpFor(wireId typeId, rt reflect.Type, name string, inProg
 			}
 
 		case reflect.Map:
-			name = "element of " + name
 			keyId := dec.wireType[wireId].MapT.Key
 			elemId := dec.wireType[wireId].MapT.Elem
-			keyOp, keyIndir := dec.decOpFor(keyId, t.Key(), name, inProgress)
-			elemOp, elemIndir := dec.decOpFor(elemId, t.Elem(), name, inProgress)
+			keyOp, keyIndir := dec.decOpFor(keyId, t.Key(), "key of "+name, inProgress)
+			elemOp, elemIndir := dec.decOpFor(elemId, t.Elem(), "element of "+name, inProgress)
 			ovfl := overflow(name)
 			op = func(i *decInstr, state *decoderState, p unsafe.Pointer) {
 				up := unsafe.Pointer(p)
@@ -1151,7 +1149,7 @@ func (dec *Decoder) compileDec(remoteId typeId, ut *userTypeInfo) (engine *decEn
 
 // getDecEnginePtr returns the engine for the specified type.
 func (dec *Decoder) getDecEnginePtr(remoteId typeId, ut *userTypeInfo) (enginePtr **decEngine, err error) {
-	rt := ut.base
+	rt := ut.user
 	decoderMap, ok := dec.decoderCache[rt]
 	if !ok {
 		decoderMap = make(map[typeId]**decEngine)
diff --git a/libgo/go/encoding/gob/encoder_test.go b/libgo/go/encoding/gob/encoder_test.go
index 9a62cf9c2ad..3bfae30f39a 100644
--- a/libgo/go/encoding/gob/encoder_test.go
+++ b/libgo/go/encoding/gob/encoder_test.go
@@ -685,3 +685,54 @@ func TestSliceIncompatibility(t *testing.T) {
 		t.Error("expected compatibility error")
 	}
 }
+
+// Mutually recursive slices of structs caused problems.
+type Bug3 struct {
+	Num      int
+	Children []*Bug3
+}
+
+func TestGobPtrSlices(t *testing.T) {
+	in := []*Bug3{
+		&Bug3{1, nil},
+		&Bug3{2, nil},
+	}
+	b := new(bytes.Buffer)
+	err := NewEncoder(b).Encode(&in)
+	if err != nil {
+		t.Fatal("encode:", err)
+	}
+
+	var out []*Bug3
+	err = NewDecoder(b).Decode(&out)
+	if err != nil {
+		t.Fatal("decode:", err)
+	}
+	if !reflect.DeepEqual(in, out) {
+		t.Fatal("got %v; wanted %v", out, in)
+	}
+}
+
+// getDecEnginePtr cached engine for ut.base instead of ut.user so we passed
+// a *map and then tried to reuse its engine to decode the inner map.
+func TestPtrToMapOfMap(t *testing.T) {
+	Register(make(map[string]interface{}))
+	subdata := make(map[string]interface{})
+	subdata["bar"] = "baz"
+	data := make(map[string]interface{})
+	data["foo"] = subdata
+
+	b := new(bytes.Buffer)
+	err := NewEncoder(b).Encode(data)
+	if err != nil {
+		t.Fatal("encode:", err)
+	}
+	var newData map[string]interface{}
+	err = NewDecoder(b).Decode(&newData)
+	if err != nil {
+		t.Fatal("decode:", err)
+	}
+	if !reflect.DeepEqual(data, newData) {
+		t.Fatalf("expected %v got %v", data, newData)
+	}
+}
diff --git a/libgo/go/encoding/gob/type.go b/libgo/go/encoding/gob/type.go
index 39006efdb2d..0dd7a0a770e 100644
--- a/libgo/go/encoding/gob/type.go
+++ b/libgo/go/encoding/gob/type.go
@@ -152,6 +152,10 @@ var idToType = make(map[typeId]gobType)
 var builtinIdToType map[typeId]gobType // set in init() after builtins are established
 
 func setTypeId(typ gobType) {
+	// When building recursive types, someone may get there before us.
+	if typ.id() != 0 {
+		return
+	}
 	nextId++
 	typ.setId(nextId)
 	idToType[nextId] = typ
@@ -346,6 +350,11 @@ func newSliceType(name string) *sliceType {
 func (s *sliceType) init(elem gobType) {
 	// Set our type id before evaluating the element's, in case it's our own.
 	setTypeId(s)
+	// See the comments about ids in newTypeObject. Only slices and
+	// structs have mutual recursion.
+	if elem.id() == 0 {
+		setTypeId(elem)
+	}
 	s.Elem = elem.id()
 }
 
@@ -503,6 +512,13 @@ func newTypeObject(name string, ut *userTypeInfo, rt reflect.Type) (gobType, err
 			if err != nil {
 				return nil, err
 			}
+			// Some mutually recursive types can cause us to be here while
+			// still defining the element. Fix the element type id here.
+			// We could do this more neatly by setting the id at the start of
+			// building every type, but that would break binary compatibility.
+			if gt.id() == 0 {
+				setTypeId(gt)
+			}
 			st.Field = append(st.Field, &fieldType{f.Name, gt.id()})
 		}
 		return st, nil
diff --git a/libgo/go/encoding/json/decode.go b/libgo/go/encoding/json/decode.go
index 87076b53dc0..110c6fd6238 100644
--- a/libgo/go/encoding/json/decode.go
+++ b/libgo/go/encoding/json/decode.go
@@ -496,6 +496,12 @@ func (d *decodeState) object(v reflect.Value) {
 					// Pretend this field doesn't exist.
 					continue
 				}
+				if sf.Anonymous {
+					// Pretend this field doesn't exist,
+					// so that we can do a good job with
+					// these in a later version.
+					continue
+				}
 				// First, tag match
 				tagName, _ := parseTag(tag)
 				if tagName == key {
@@ -963,3 +969,11 @@ func unquoteBytes(s []byte) (t []byte, ok bool) {
 	}
 	return b[0:w], true
 }
+
+// The following is issue 3069.
+
+// BUG(rsc): This package ignores anonymous (embedded) struct fields
+// during encoding and decoding.  A future version may assign meaning
+// to them.  To force an anonymous field to be ignored in all future
+// versions of this package, use an explicit `json:"-"` tag in the struct
+// definition.
diff --git a/libgo/go/encoding/json/decode_test.go b/libgo/go/encoding/json/decode_test.go
index 775becfa7c9..0eec586a9bb 100644
--- a/libgo/go/encoding/json/decode_test.go
+++ b/libgo/go/encoding/json/decode_test.go
@@ -619,3 +619,32 @@ func TestRefUnmarshal(t *testing.T) {
 		t.Errorf("got %+v, want %+v", got, want)
 	}
 }
+
+// Test that anonymous fields are ignored.
+// We may assign meaning to them later.
+func TestAnonymous(t *testing.T) {
+	type S struct {
+		T
+		N int
+	}
+
+	data, err := Marshal(new(S))
+	if err != nil {
+		t.Fatalf("Marshal: %v", err)
+	}
+	want := `{"N":0}`
+	if string(data) != want {
+		t.Fatalf("Marshal = %#q, want %#q", string(data), want)
+	}
+
+	var s S
+	if err := Unmarshal([]byte(`{"T": 1, "T": {"Y": 1}, "N": 2}`), &s); err != nil {
+		t.Fatalf("Unmarshal: %v", err)
+	}
+	if s.N != 2 {
+		t.Fatal("Unmarshal: did not set N")
+	}
+	if s.T.Y != 0 {
+		t.Fatal("Unmarshal: did set T.Y")
+	}
+}
diff --git a/libgo/go/encoding/json/encode.go b/libgo/go/encoding/json/encode.go
index 83e73c09cb4..8a794b79bd5 100644
--- a/libgo/go/encoding/json/encode.go
+++ b/libgo/go/encoding/json/encode.go
@@ -538,6 +538,11 @@ func encodeFields(t reflect.Type) []encodeField {
 		if f.PkgPath != "" {
 			continue
 		}
+		if f.Anonymous {
+			// We want to do a better job with these later,
+			// so for now pretend they don't exist.
+			continue
+		}
 		var ef encodeField
 		ef.i = i
 		ef.tag = f.Name
diff --git a/libgo/go/encoding/xml/marshal.go b/libgo/go/encoding/xml/marshal.go
index a96c523d553..6c3170bdda3 100644
--- a/libgo/go/encoding/xml/marshal.go
+++ b/libgo/go/encoding/xml/marshal.go
@@ -57,35 +57,14 @@ const (
 //       if the field value is empty. The empty values are false, 0, any
 //       nil pointer or interface value, and any array, slice, map, or
 //       string of length zero.
+//     - a non-pointer anonymous struct field is handled as if the
+//       fields of its value were part of the outer struct.
 //
 // If a field uses a tag "a>b>c", then the element c will be nested inside
 // parent elements a and b.  Fields that appear next to each other that name
-// the same parent will be enclosed in one XML element.  For example:
+// the same parent will be enclosed in one XML element.
 //
-//	type Result struct {
-//		XMLName   xml.Name `xml:"result"`
-//		Id        int      `xml:"id,attr"`
-//		FirstName string   `xml:"person>name>first"`
-//		LastName  string   `xml:"person>name>last"`
-//		Age       int      `xml:"person>age"`
-//		Height    float    `xml:"person>height,omitempty"`
-//		Married   bool     `xml:"person>married"`
-//	}
-//
-//	xml.Marshal(&Result{Id: 13, FirstName: "John", LastName: "Doe", Age: 42})
-//
-// would be marshalled as:
-//
-//	<result>
-//		<person id="13">
-//			<name>
-//				<first>John</first>
-//				<last>Doe</last>
-//			</name>
-//			<age>42</age>
-//			<married>false</married>
-//		</person>
-//	</result>
+// See MarshalIndent for an example.
 //
 // Marshal will return an error if asked to marshal a channel, function, or map.
 func Marshal(v interface{}) ([]byte, error) {
@@ -96,6 +75,22 @@ func Marshal(v interface{}) ([]byte, error) {
 	return b.Bytes(), nil
 }
 
+// MarshalIndent works like Marshal, but each XML element begins on a new
+// indented line that starts with prefix and is followed by one or more
+// copies of indent according to the nesting depth.
+func MarshalIndent(v interface{}, prefix, indent string) ([]byte, error) {
+	var b bytes.Buffer
+	enc := NewEncoder(&b)
+	enc.prefix = prefix
+	enc.indent = indent
+	err := enc.marshalValue(reflect.ValueOf(v), nil)
+	enc.Flush()
+	if err != nil {
+		return nil, err
+	}
+	return b.Bytes(), nil
+}
+
 // An Encoder writes XML data to an output stream.
 type Encoder struct {
 	printer
@@ -103,7 +98,7 @@ type Encoder struct {
 
 // NewEncoder returns a new encoder that writes to w.
 func NewEncoder(w io.Writer) *Encoder {
-	return &Encoder{printer{bufio.NewWriter(w)}}
+	return &Encoder{printer{Writer: bufio.NewWriter(w)}}
 }
 
 // Encode writes the XML encoding of v to the stream.
@@ -118,8 +113,14 @@ func (enc *Encoder) Encode(v interface{}) error {
 
 type printer struct {
 	*bufio.Writer
+	indent     string
+	prefix     string
+	depth      int
+	indentedIn bool
 }
 
+// marshalValue writes one or more XML elements representing val.
+// If val was obtained from a struct field, finfo must have its details.
 func (p *printer) marshalValue(val reflect.Value, finfo *fieldInfo) error {
 	if !val.IsValid() {
 		return nil
@@ -177,6 +178,7 @@ func (p *printer) marshalValue(val reflect.Value, finfo *fieldInfo) error {
 		}
 	}
 
+	p.writeIndent(1)
 	p.WriteByte('<')
 	p.WriteString(name)
 
@@ -216,6 +218,7 @@ func (p *printer) marshalValue(val reflect.Value, finfo *fieldInfo) error {
 		return err
 	}
 
+	p.writeIndent(-1)
 	p.WriteByte('<')
 	p.WriteByte('/')
 	p.WriteString(name)
@@ -294,6 +297,7 @@ func (p *printer) marshalStruct(tinfo *typeInfo, val reflect.Value) error {
 			if vf.Len() == 0 {
 				continue
 			}
+			p.writeIndent(0)
 			p.WriteString("<!--")
 			dashDash := false
 			dashLast := false
@@ -352,6 +356,33 @@ func (p *printer) marshalStruct(tinfo *typeInfo, val reflect.Value) error {
 	return nil
 }
 
+func (p *printer) writeIndent(depthDelta int) {
+	if len(p.prefix) == 0 && len(p.indent) == 0 {
+		return
+	}
+	if depthDelta < 0 {
+		p.depth--
+		if p.indentedIn {
+			p.indentedIn = false
+			return
+		}
+		p.indentedIn = false
+	}
+	p.WriteByte('\n')
+	if len(p.prefix) > 0 {
+		p.WriteString(p.prefix)
+	}
+	if len(p.indent) > 0 {
+		for i := 0; i < p.depth; i++ {
+			p.WriteString(p.indent)
+		}
+	}
+	if depthDelta > 0 {
+		p.depth++
+		p.indentedIn = true
+	}
+}
+
 type parentStack struct {
 	*printer
 	stack []string
@@ -367,20 +398,20 @@ func (s *parentStack) trim(parents []string) {
 			break
 		}
 	}
-
 	for i := len(s.stack) - 1; i >= split; i-- {
+		s.writeIndent(-1)
 		s.WriteString("</")
 		s.WriteString(s.stack[i])
 		s.WriteByte('>')
 	}
-
 	s.stack = parents[:split]
 }
 
 // push adds parent elements to the stack and writes open tags.
 func (s *parentStack) push(parents []string) {
 	for i := 0; i < len(parents); i++ {
-		s.WriteString("<")
+		s.writeIndent(1)
+		s.WriteByte('<')
 		s.WriteString(parents[i])
 		s.WriteByte('>')
 	}
diff --git a/libgo/go/encoding/xml/read.go b/libgo/go/encoding/xml/read.go
index b5a3426a328..c2168242091 100644
--- a/libgo/go/encoding/xml/read.go
+++ b/libgo/go/encoding/xml/read.go
@@ -25,58 +25,6 @@ import (
 // slice, or string. Well-formed data that does not fit into v is
 // discarded.
 //
-// For example, given these definitions:
-//
-//	type Email struct {
-//		Where string `xml:",attr"`
-//		Addr  string
-//	}
-//
-//	type Result struct {
-//		XMLName xml.Name `xml:"result"`
-//		Name	string
-//		Phone	string
-//		Email	[]Email
-//		Groups  []string `xml:"group>value"`
-//	}
-//
-//	result := Result{Name: "name", Phone: "phone", Email: nil}
-//
-// unmarshalling the XML input
-//
-//	<result>
-//		<email where="home">
-//			<addr>gre@example.com</addr>
-//		</email>
-//		<email where='work'>
-//			<addr>gre@work.com</addr>
-//		</email>
-//		<name>Grace R. Emlin</name>
-// 		<group>
-// 			<value>Friends</value>
-// 			<value>Squash</value>
-// 		</group>
-//		<address>123 Main Street</address>
-//	</result>
-//
-// via Unmarshal(data, &result) is equivalent to assigning
-//
-//	r = Result{
-//		xml.Name{Local: "result"},
-//		"Grace R. Emlin", // name
-//		"phone",	  // no phone given
-//		[]Email{
-//			Email{"home", "gre@example.com"},
-//			Email{"work", "gre@work.com"},
-//		},
-//		[]string{"Friends", "Squash"},
-//	}
-//
-// Note that the field r.Phone has not been modified and
-// that the XML <address> element was discarded. Also, the field
-// Groups was assigned considering the element path provided in the
-// field tag.
-//
 // Because Unmarshal uses the reflect package, it can only assign
 // to exported (upper case) fields.  Unmarshal uses a case-sensitive
 // comparison to match XML element names to tag values and struct
@@ -133,6 +81,9 @@ import (
 //      of the above rules and the struct has a field with tag ",any",
 //      unmarshal maps the sub-element to that struct field.
 //
+//   * A non-pointer anonymous struct field is handled as if the
+//      fields of its value were part of the outer struct.
+//
 //   * A struct field with tag "-" is never unmarshalled into.
 //
 // Unmarshal maps an XML element to a string or []byte by saving the
diff --git a/libgo/go/errors/errors_test.go b/libgo/go/errors/errors_test.go
index c537eeb6251..63c05d7185b 100644
--- a/libgo/go/errors/errors_test.go
+++ b/libgo/go/errors/errors_test.go
@@ -5,29 +5,49 @@
 package errors_test
 
 import (
-	. "errors"
+	"errors"
+	"fmt"
 	"testing"
 )
 
 func TestNewEqual(t *testing.T) {
 	// Different allocations should not be equal.
-	if New("abc") == New("abc") {
+	if errors.New("abc") == errors.New("abc") {
 		t.Errorf(`New("abc") == New("abc")`)
 	}
-	if New("abc") == New("xyz") {
+	if errors.New("abc") == errors.New("xyz") {
 		t.Errorf(`New("abc") == New("xyz")`)
 	}
 
 	// Same allocation should be equal to itself (not crash).
-	err := New("jkl")
+	err := errors.New("jkl")
 	if err != err {
 		t.Errorf(`err != err`)
 	}
 }
 
 func TestErrorMethod(t *testing.T) {
-	err := New("abc")
+	err := errors.New("abc")
 	if err.Error() != "abc" {
 		t.Errorf(`New("abc").Error() = %q, want %q`, err.Error(), "abc")
 	}
 }
+
+func ExampleNew() {
+	err := errors.New("emit macho dwarf: elf header corrupted")
+	if err != nil {
+		fmt.Print(err)
+	}
+	// Output: emit macho dwarf: elf header corrupted
+}
+
+// The fmt package's Errorf function lets us use the package's formatting
+// features to create descriptive error messages.
+func ExampleNew_errorf() {
+	const name, id = "bimmler", 17
+	err := fmt.Errorf("user %q (id %d) not found", name, id)
+	if err != nil {
+		fmt.Print(err)
+	}
+	// Output: user "bimmler" (id 17) not found
+}
diff --git a/libgo/go/exp/inotify/inotify_linux_test.go b/libgo/go/exp/inotify/inotify_linux_test.go
index c2160fc6537..d41d66bfacd 100644
--- a/libgo/go/exp/inotify/inotify_linux_test.go
+++ b/libgo/go/exp/inotify/inotify_linux_test.go
@@ -7,6 +7,7 @@
 package inotify
 
 import (
+	"io/ioutil"
 	"os"
 	"testing"
 	"time"
@@ -16,16 +17,19 @@ func TestInotifyEvents(t *testing.T) {
 	// Create an inotify watcher instance and initialize it
 	watcher, err := NewWatcher()
 	if err != nil {
-		t.Fatalf("NewWatcher() failed: %s", err)
+		t.Fatalf("NewWatcher failed: %s", err)
 	}
 
-	t.Logf("NEEDS TO BE CONVERTED TO NEW GO TOOL") // TODO
-	return
+	dir, err := ioutil.TempDir("", "inotify")
+	if err != nil {
+		t.Fatalf("TempDir failed: %s", err)
+	}
+	defer os.RemoveAll(dir)
 
 	// Add a watch for "_test"
-	err = watcher.Watch("_test")
+	err = watcher.Watch(dir)
 	if err != nil {
-		t.Fatalf("Watcher.Watch() failed: %s", err)
+		t.Fatalf("Watch failed: %s", err)
 	}
 
 	// Receive errors on the error channel on a separate goroutine
@@ -35,7 +39,7 @@ func TestInotifyEvents(t *testing.T) {
 		}
 	}()
 
-	const testFile string = "_test/TestInotifyEvents.testfile"
+	testFile := dir + "/TestInotifyEvents.testfile"
 
 	// Receive events on the event channel on a separate goroutine
 	eventstream := watcher.Event
@@ -58,7 +62,7 @@ func TestInotifyEvents(t *testing.T) {
 	// This should add at least one event to the inotify event queue
 	_, err = os.OpenFile(testFile, os.O_WRONLY|os.O_CREATE, 0666)
 	if err != nil {
-		t.Fatalf("creating test file failed: %s", err)
+		t.Fatalf("creating test file: %s", err)
 	}
 
 	// We expect this event to be received almost immediately, but let's wait 1 s to be sure
@@ -95,7 +99,7 @@ func TestInotifyClose(t *testing.T) {
 		t.Fatal("double Close() test failed: second Close() call didn't return")
 	}
 
-	err := watcher.Watch("_test")
+	err := watcher.Watch(os.TempDir())
 	if err == nil {
 		t.Fatal("expected error on Watch() after Close(), got nil")
 	}
diff --git a/libgo/go/exp/norm/composition.go b/libgo/go/exp/norm/composition.go
index ccff4670602..2cbe1ac730e 100644
--- a/libgo/go/exp/norm/composition.go
+++ b/libgo/go/exp/norm/composition.go
@@ -66,6 +66,18 @@ func (rb *reorderBuffer) flush(out []byte) []byte {
 	return out
 }
 
+// flushCopy copies the normalized segment to buf and resets rb.
+// It returns the number of bytes written to buf.
+func (rb *reorderBuffer) flushCopy(buf []byte) int {
+	p := 0
+	for i := 0; i < rb.nrune; i++ {
+		runep := rb.rune[i]
+		p += copy(buf[p:], rb.byte[runep.pos:runep.pos+runep.size])
+	}
+	rb.reset()
+	return p
+}
+
 // insertOrdered inserts a rune in the buffer, ordered by Canonical Combining Class.
 // It returns false if the buffer is not large enough to hold the rune.
 // It is used internally by insert and insertString only.
@@ -96,32 +108,41 @@ func (rb *reorderBuffer) insertOrdered(info runeInfo) bool {
 // insert inserts the given rune in the buffer ordered by CCC.
 // It returns true if the buffer was large enough to hold the decomposed rune.
 func (rb *reorderBuffer) insert(src input, i int, info runeInfo) bool {
-	if info.size == 3 {
-		if rune := src.hangul(i); rune != 0 {
-			return rb.decomposeHangul(rune)
-		}
+	if rune := src.hangul(i); rune != 0 {
+		return rb.decomposeHangul(rune)
 	}
 	if info.hasDecomposition() {
-		dcomp := info.decomposition()
-		rb.tmpBytes = inputBytes(dcomp)
-		for i := 0; i < len(dcomp); {
-			info = rb.f.info(&rb.tmpBytes, i)
-			pos := rb.nbyte
-			if !rb.insertOrdered(info) {
-				return false
-			}
-			end := i + int(info.size)
-			copy(rb.byte[pos:], dcomp[i:end])
-			i = end
-		}
-	} else {
-		// insertOrder changes nbyte
+		return rb.insertDecomposed(info.decomposition())
+	}
+	return rb.insertSingle(src, i, info)
+}
+
+// insertDecomposed inserts an entry in to the reorderBuffer for each rune
+// in dcomp.  dcomp must be a sequence of decomposed UTF-8-encoded runes.
+func (rb *reorderBuffer) insertDecomposed(dcomp []byte) bool {
+	saveNrune, saveNbyte := rb.nrune, rb.nbyte
+	rb.tmpBytes = inputBytes(dcomp)
+	for i := 0; i < len(dcomp); {
+		info := rb.f.info(&rb.tmpBytes, i)
 		pos := rb.nbyte
 		if !rb.insertOrdered(info) {
+			rb.nrune, rb.nbyte = saveNrune, saveNbyte
 			return false
 		}
-		src.copySlice(rb.byte[pos:], i, i+int(info.size))
+		i += copy(rb.byte[pos:], dcomp[i:i+int(info.size)])
+	}
+	return true
+}
+
+// insertSingle inserts an entry in the reorderBuffer for the rune at
+// position i. info is the runeInfo for the rune at position i.
+func (rb *reorderBuffer) insertSingle(src input, i int, info runeInfo) bool {
+	// insertOrder changes nbyte
+	pos := rb.nbyte
+	if !rb.insertOrdered(info) {
+		return false
 	}
+	src.copySlice(rb.byte[pos:], i, i+int(info.size))
 	return true
 }
 
@@ -182,8 +203,12 @@ const (
 	jamoLVTCount = 19 * 21 * 28
 )
 
-// Caller must verify that len(b) >= 3.
+const hangulUTF8Size = 3
+
 func isHangul(b []byte) bool {
+	if len(b) < hangulUTF8Size {
+		return false
+	}
 	b0 := b[0]
 	if b0 < hangulBase0 {
 		return false
@@ -202,8 +227,10 @@ func isHangul(b []byte) bool {
 	return b1 == hangulEnd1 && b[2] < hangulEnd2
 }
 
-// Caller must verify that len(b) >= 3.
 func isHangulString(b string) bool {
+	if len(b) < hangulUTF8Size {
+		return false
+	}
 	b0 := b[0]
 	if b0 < hangulBase0 {
 		return false
@@ -234,6 +261,22 @@ func isHangulWithoutJamoT(b []byte) bool {
 	return c < jamoLVTCount && c%jamoTCount == 0
 }
 
+// decomposeHangul writes the decomposed Hangul to buf and returns the number
+// of bytes written.  len(buf) should be at least 9.
+func decomposeHangul(buf []byte, r rune) int {
+	const JamoUTF8Len = 3
+	r -= hangulBase
+	x := r % jamoTCount
+	r /= jamoTCount
+	utf8.EncodeRune(buf, jamoLBase+r/jamoVCount)
+	utf8.EncodeRune(buf[JamoUTF8Len:], jamoVBase+r%jamoVCount)
+	if x != 0 {
+		utf8.EncodeRune(buf[2*JamoUTF8Len:], jamoTBase+x)
+		return 3 * JamoUTF8Len
+	}
+	return 2 * JamoUTF8Len
+}
+
 // decomposeHangul algorithmically decomposes a Hangul rune into
 // its Jamo components.
 // See http://unicode.org/reports/tr15/#Hangul for details on decomposing Hangul.
diff --git a/libgo/go/exp/norm/composition_test.go b/libgo/go/exp/norm/composition_test.go
index e32380d7afa..9de9eacfd65 100644
--- a/libgo/go/exp/norm/composition_test.go
+++ b/libgo/go/exp/norm/composition_test.go
@@ -47,14 +47,14 @@ func runTests(t *testing.T, name string, fm Form, f insertFunc, tests []TestCase
 	}
 }
 
-func TestFlush(t *testing.T) {
+type flushFunc func(rb *reorderBuffer) []byte
+
+func testFlush(t *testing.T, name string, fn flushFunc) {
 	rb := reorderBuffer{}
 	rb.init(NFC, nil)
-	out := make([]byte, 0)
-
-	out = rb.flush(out)
+	out := fn(&rb)
 	if len(out) != 0 {
-		t.Errorf("wrote bytes on flush of empty buffer. (len(out) = %d)", len(out))
+		t.Errorf("%s: wrote bytes on flush of empty buffer. (len(out) = %d)", name, len(out))
 	}
 
 	for _, r := range []rune("world!") {
@@ -65,16 +65,32 @@ func TestFlush(t *testing.T) {
 	out = rb.flush(out)
 	want := "Hello world!"
 	if string(out) != want {
-		t.Errorf(`output after flush was "%s"; want "%s"`, string(out), want)
+		t.Errorf(`%s: output after flush was "%s"; want "%s"`, name, string(out), want)
 	}
 	if rb.nrune != 0 {
-		t.Errorf("flush: non-null size of info buffer (rb.nrune == %d)", rb.nrune)
+		t.Errorf("%s: non-null size of info buffer (rb.nrune == %d)", name, rb.nrune)
 	}
 	if rb.nbyte != 0 {
-		t.Errorf("flush: non-null size of byte buffer (rb.nbyte == %d)", rb.nbyte)
+		t.Errorf("%s: non-null size of byte buffer (rb.nbyte == %d)", name, rb.nbyte)
 	}
 }
 
+func flushF(rb *reorderBuffer) []byte {
+	out := make([]byte, 0)
+	return rb.flush(out)
+}
+
+func flushCopyF(rb *reorderBuffer) []byte {
+	out := make([]byte, MaxSegmentSize)
+	n := rb.flushCopy(out)
+	return out[:n]
+}
+
+func TestFlush(t *testing.T) {
+	testFlush(t, "flush", flushF)
+	testFlush(t, "flushCopy", flushCopyF)
+}
+
 var insertTests = []TestCase{
 	{[]rune{'a'}, []rune{'a'}},
 	{[]rune{0x300}, []rune{0x300}},
diff --git a/libgo/go/exp/norm/input.go b/libgo/go/exp/norm/input.go
index 5c0968ba58c..9c564d67718 100644
--- a/libgo/go/exp/norm/input.go
+++ b/libgo/go/exp/norm/input.go
@@ -7,7 +7,7 @@ package norm
 import "unicode/utf8"
 
 type input interface {
-	skipASCII(p int) int
+	skipASCII(p, max int) int
 	skipNonStarter(p int) int
 	appendSlice(buf []byte, s, e int) []byte
 	copySlice(buf []byte, s, e int)
@@ -18,8 +18,8 @@ type input interface {
 
 type inputString string
 
-func (s inputString) skipASCII(p int) int {
-	for ; p < len(s) && s[p] < utf8.RuneSelf; p++ {
+func (s inputString) skipASCII(p, max int) int {
+	for ; p < max && s[p] < utf8.RuneSelf; p++ {
 	}
 	return p
 }
@@ -59,8 +59,8 @@ func (s inputString) hangul(p int) rune {
 
 type inputBytes []byte
 
-func (s inputBytes) skipASCII(p int) int {
-	for ; p < len(s) && s[p] < utf8.RuneSelf; p++ {
+func (s inputBytes) skipASCII(p, max int) int {
+	for ; p < max && s[p] < utf8.RuneSelf; p++ {
 	}
 	return p
 }
diff --git a/libgo/go/exp/norm/iter.go b/libgo/go/exp/norm/iter.go
new file mode 100644
index 00000000000..761ba90cdd4
--- /dev/null
+++ b/libgo/go/exp/norm/iter.go
@@ -0,0 +1,286 @@
+// 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.
+
+package norm
+
+const MaxSegmentSize = maxByteBufferSize
+
+// An Iter iterates over a string or byte slice, while normalizing it
+// to a given Form.
+type Iter struct {
+	rb   reorderBuffer
+	info runeInfo // first character saved from previous iteration
+	next iterFunc // implementation of next depends on form
+
+	p        int // current position in input source
+	outStart int // start of current segment in output buffer
+	inStart  int // start of current segment in input source
+	maxp     int // position in output buffer after which not to start a new segment
+	maxseg   int // for tracking an excess of combining characters
+
+	tccc uint8
+	done bool
+}
+
+type iterFunc func(*Iter, []byte) int
+
+// SetInput initializes i to iterate over src after normalizing it to Form f.
+func (i *Iter) SetInput(f Form, src []byte) {
+	i.rb.init(f, src)
+	if i.rb.f.composing {
+		i.next = nextComposed
+	} else {
+		i.next = nextDecomposed
+	}
+	i.p = 0
+	if i.done = len(src) == 0; !i.done {
+		i.info = i.rb.f.info(i.rb.src, i.p)
+	}
+}
+
+// SetInputString initializes i to iterate over src after normalizing it to Form f.
+func (i *Iter) SetInputString(f Form, src string) {
+	i.rb.initString(f, src)
+	if i.rb.f.composing {
+		i.next = nextComposed
+	} else {
+		i.next = nextDecomposed
+	}
+	i.p = 0
+	if i.done = len(src) == 0; !i.done {
+		i.info = i.rb.f.info(i.rb.src, i.p)
+	}
+}
+
+// Pos returns the byte position at which the next call to Next will commence processing.
+func (i *Iter) Pos() int {
+	return i.p
+}
+
+// Done returns true if there is no more input to process.
+func (i *Iter) Done() bool {
+	return i.done
+}
+
+// Next writes f(i.input[i.Pos():n]...) to buffer buf, where n is the
+// largest boundary of i.input such that the result fits in buf.  
+// It returns the number of bytes written to buf.
+// len(buf) should be at least MaxSegmentSize. 
+// Done must be false before calling Next.
+func (i *Iter) Next(buf []byte) int {
+	return i.next(i, buf)
+}
+
+func (i *Iter) initNext(outn, inStart int) {
+	i.outStart = 0
+	i.inStart = inStart
+	i.maxp = outn - MaxSegmentSize
+	i.maxseg = MaxSegmentSize
+}
+
+// setStart resets the start of the new segment to the given position.
+// It returns true if there is not enough room for the new segment.
+func (i *Iter) setStart(outp, inp int) bool {
+	if outp > i.maxp {
+		return true
+	}
+	i.outStart = outp
+	i.inStart = inp
+	i.maxseg = outp + MaxSegmentSize
+	return false
+}
+
+func min(a, b int) int {
+	if a < b {
+		return a
+	}
+	return b
+}
+
+// nextDecomposed is the implementation of Next for forms NFD and NFKD.
+func nextDecomposed(i *Iter, out []byte) int {
+	var outp int
+	i.initNext(len(out), i.p)
+doFast:
+	inCopyStart, outCopyStart := i.p, outp // invariant xCopyStart <= i.xStart
+	for {
+		if sz := int(i.info.size); sz <= 1 {
+			// ASCII or illegal byte.  Either way, advance by 1.
+			i.p++
+			outp++
+			max := min(i.rb.nsrc, len(out)-outp+i.p)
+			if np := i.rb.src.skipASCII(i.p, max); np > i.p {
+				outp += np - i.p
+				i.p = np
+				if i.p >= i.rb.nsrc {
+					break
+				}
+				// ASCII may combine with consecutive runes.
+				if i.setStart(outp-1, i.p-1) {
+					i.p--
+					outp--
+					i.info.size = 1
+					break
+				}
+			}
+		} else if d := i.info.decomposition(); d != nil {
+			i.rb.src.copySlice(out[outCopyStart:], inCopyStart, i.p)
+			p := outp + len(d)
+			if p > i.maxseg && i.setStart(outp, i.p) {
+				return outp
+			}
+			copy(out[outp:], d)
+			outp = p
+			i.p += sz
+			inCopyStart, outCopyStart = i.p, outp
+		} else if r := i.rb.src.hangul(i.p); r != 0 {
+			i.rb.src.copySlice(out[outCopyStart:], inCopyStart, i.p)
+			for {
+				outp += decomposeHangul(out[outp:], r)
+				i.p += hangulUTF8Size
+				if r = i.rb.src.hangul(i.p); r == 0 {
+					break
+				}
+				if i.setStart(outp, i.p) {
+					return outp
+				}
+			}
+			inCopyStart, outCopyStart = i.p, outp
+		} else {
+			p := outp + sz
+			if p > i.maxseg && i.setStart(outp, i.p) {
+				break
+			}
+			outp = p
+			i.p += sz
+		}
+		if i.p >= i.rb.nsrc {
+			break
+		}
+		prevCC := i.info.tccc
+		i.info = i.rb.f.info(i.rb.src, i.p)
+		if cc := i.info.ccc; cc == 0 {
+			if i.setStart(outp, i.p) {
+				break
+			}
+		} else if cc < prevCC {
+			goto doNorm
+		}
+	}
+	if inCopyStart != i.p {
+		i.rb.src.copySlice(out[outCopyStart:], inCopyStart, i.p)
+	}
+	i.done = i.p >= i.rb.nsrc
+	return outp
+doNorm:
+	// Insert what we have decomposed so far in the reorderBuffer.
+	// As we will only reorder, there will always be enough room.
+	i.rb.src.copySlice(out[outCopyStart:], inCopyStart, i.p)
+	if !i.rb.insertDecomposed(out[i.outStart:outp]) {
+		// Start over to prevent decompositions from crossing segment boundaries.
+		// This is a rare occurance.
+		i.p = i.inStart
+		i.info = i.rb.f.info(i.rb.src, i.p)
+	}
+	outp = i.outStart
+	for {
+		if !i.rb.insert(i.rb.src, i.p, i.info) {
+			break
+		}
+		if i.p += int(i.info.size); i.p >= i.rb.nsrc {
+			outp += i.rb.flushCopy(out[outp:])
+			i.done = true
+			return outp
+		}
+		i.info = i.rb.f.info(i.rb.src, i.p)
+		if i.info.ccc == 0 {
+			break
+		}
+	}
+	// new segment or too many combining characters: exit normalization
+	if outp += i.rb.flushCopy(out[outp:]); i.setStart(outp, i.p) {
+		return outp
+	}
+	goto doFast
+}
+
+// nextComposed is the implementation of Next for forms NFC and NFKC.
+func nextComposed(i *Iter, out []byte) int {
+	var outp int
+	i.initNext(len(out), i.p)
+doFast:
+	inCopyStart, outCopyStart := i.p, outp // invariant xCopyStart <= i.xStart
+	var prevCC uint8
+	for {
+		if !i.info.isYesC() {
+			goto doNorm
+		}
+		if cc := i.info.ccc; cc == 0 {
+			if i.setStart(outp, i.p) {
+				break
+			}
+		} else if cc < prevCC {
+			goto doNorm
+		}
+		prevCC = i.info.tccc
+		sz := int(i.info.size)
+		if sz == 0 {
+			sz = 1 // illegal rune: copy byte-by-byte
+		}
+		p := outp + sz
+		if p > i.maxseg && i.setStart(outp, i.p) {
+			break
+		}
+		outp = p
+		i.p += sz
+		max := min(i.rb.nsrc, len(out)-outp+i.p)
+		if np := i.rb.src.skipASCII(i.p, max); np > i.p {
+			outp += np - i.p
+			i.p = np
+			if i.p >= i.rb.nsrc {
+				break
+			}
+			// ASCII may combine with consecutive runes.
+			if i.setStart(outp-1, i.p-1) {
+				i.p--
+				outp--
+				i.info = runeInfo{size: 1}
+				break
+			}
+		}
+		if i.p >= i.rb.nsrc {
+			break
+		}
+		i.info = i.rb.f.info(i.rb.src, i.p)
+	}
+	if inCopyStart != i.p {
+		i.rb.src.copySlice(out[outCopyStart:], inCopyStart, i.p)
+	}
+	i.done = i.p >= i.rb.nsrc
+	return outp
+doNorm:
+	i.rb.src.copySlice(out[outCopyStart:], inCopyStart, i.inStart)
+	outp, i.p = i.outStart, i.inStart
+	i.info = i.rb.f.info(i.rb.src, i.p)
+	for {
+		if !i.rb.insert(i.rb.src, i.p, i.info) {
+			break
+		}
+		if i.p += int(i.info.size); i.p >= i.rb.nsrc {
+			i.rb.compose()
+			outp += i.rb.flushCopy(out[outp:])
+			i.done = true
+			return outp
+		}
+		i.info = i.rb.f.info(i.rb.src, i.p)
+		if i.info.boundaryBefore() {
+			break
+		}
+	}
+	i.rb.compose()
+	if outp += i.rb.flushCopy(out[outp:]); i.setStart(outp, i.p) {
+		return outp
+	}
+	goto doFast
+}
diff --git a/libgo/go/exp/norm/iter_test.go b/libgo/go/exp/norm/iter_test.go
new file mode 100644
index 00000000000..f6e8d817251
--- /dev/null
+++ b/libgo/go/exp/norm/iter_test.go
@@ -0,0 +1,186 @@
+// 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.
+
+package norm
+
+import (
+	"strings"
+	"testing"
+)
+
+var iterBufSizes = []int{
+	MaxSegmentSize,
+	1.5 * MaxSegmentSize,
+	2 * MaxSegmentSize,
+	3 * MaxSegmentSize,
+	100 * MaxSegmentSize,
+}
+
+func doIterNorm(f Form, buf []byte, s string) []byte {
+	acc := []byte{}
+	i := Iter{}
+	i.SetInputString(f, s)
+	for !i.Done() {
+		n := i.Next(buf)
+		acc = append(acc, buf[:n]...)
+	}
+	return acc
+}
+
+func runIterTests(t *testing.T, name string, f Form, tests []AppendTest, norm bool) {
+	for i, test := range tests {
+		in := test.left + test.right
+		gold := test.out
+		if norm {
+			gold = string(f.AppendString(nil, test.out))
+		}
+		for _, sz := range iterBufSizes {
+			buf := make([]byte, sz)
+			out := string(doIterNorm(f, buf, in))
+			if len(out) != len(gold) {
+				const msg = "%s:%d:%d: length is %d; want %d"
+				t.Errorf(msg, name, i, sz, len(out), len(gold))
+			}
+			if out != gold {
+				// Find first rune that differs and show context.
+				ir := []rune(out)
+				ig := []rune(gold)
+				for j := 0; j < len(ir) && j < len(ig); j++ {
+					if ir[j] == ig[j] {
+						continue
+					}
+					if j -= 3; j < 0 {
+						j = 0
+					}
+					for e := j + 7; j < e && j < len(ir) && j < len(ig); j++ {
+						const msg = "%s:%d:%d: runeAt(%d) = %U; want %U"
+						t.Errorf(msg, name, i, sz, j, ir[j], ig[j])
+					}
+					break
+				}
+			}
+		}
+	}
+}
+
+func rep(r rune, n int) string {
+	return strings.Repeat(string(r), n)
+}
+
+var iterTests = []AppendTest{
+	{"", ascii, ascii},
+	{"", txt_all, txt_all},
+	{"", "a" + rep(0x0300, MaxSegmentSize/2), "a" + rep(0x0300, MaxSegmentSize/2)},
+}
+
+var iterTestsD = []AppendTest{
+	{ // segment overflow on unchanged character
+		"",
+		"a" + rep(0x0300, MaxSegmentSize/2) + "\u0316",
+		"a" + rep(0x0300, MaxSegmentSize/2-1) + "\u0316\u0300",
+	},
+	{ // segment overflow on unchanged character + start value
+		"",
+		"a" + rep(0x0300, MaxSegmentSize/2+maxCombiningChars+4) + "\u0316",
+		"a" + rep(0x0300, MaxSegmentSize/2+maxCombiningChars) + "\u0316" + rep(0x300, 4),
+	},
+	{ // segment overflow on decomposition
+		"",
+		"a" + rep(0x0300, MaxSegmentSize/2-1) + "\u0340",
+		"a" + rep(0x0300, MaxSegmentSize/2),
+	},
+	{ // segment overflow on decomposition + start value
+		"",
+		"a" + rep(0x0300, MaxSegmentSize/2-1) + "\u0340" + rep(0x300, maxCombiningChars+4) + "\u0320",
+		"a" + rep(0x0300, MaxSegmentSize/2-1) + rep(0x300, maxCombiningChars+1) + "\u0320" + rep(0x300, 4),
+	},
+	{ // start value after ASCII overflow
+		"",
+		rep('a', MaxSegmentSize) + rep(0x300, maxCombiningChars+2) + "\u0320",
+		rep('a', MaxSegmentSize) + rep(0x300, maxCombiningChars) + "\u0320\u0300\u0300",
+	},
+	{ // start value after Hangul overflow
+		"",
+		rep(0xAC00, MaxSegmentSize/6) + rep(0x300, maxCombiningChars+2) + "\u0320",
+		strings.Repeat("\u1100\u1161", MaxSegmentSize/6) + rep(0x300, maxCombiningChars-1) + "\u0320" + rep(0x300, 3),
+	},
+	{ // start value after cc=0
+		"",
+		"您您" + rep(0x300, maxCombiningChars+4) + "\u0320",
+		"您您" + rep(0x300, maxCombiningChars) + "\u0320" + rep(0x300, 4),
+	},
+	{ // start value after normalization
+		"",
+		"\u0300\u0320a" + rep(0x300, maxCombiningChars+4) + "\u0320",
+		"\u0320\u0300a" + rep(0x300, maxCombiningChars) + "\u0320" + rep(0x300, 4),
+	},
+}
+
+var iterTestsC = []AppendTest{
+	{ // ordering of non-composing combining characters
+		"",
+		"\u0305\u0316",
+		"\u0316\u0305",
+	},
+	{ // segment overflow
+		"",
+		"a" + rep(0x0305, MaxSegmentSize/2+4) + "\u0316",
+		"a" + rep(0x0305, MaxSegmentSize/2-1) + "\u0316" + rep(0x305, 5),
+	},
+}
+
+func TestIterNextD(t *testing.T) {
+	runIterTests(t, "IterNextD1", NFKD, appendTests, true)
+	runIterTests(t, "IterNextD2", NFKD, iterTests, true)
+	runIterTests(t, "IterNextD3", NFKD, iterTestsD, false)
+}
+
+func TestIterNextC(t *testing.T) {
+	runIterTests(t, "IterNextC1", NFKC, appendTests, true)
+	runIterTests(t, "IterNextC2", NFKC, iterTests, true)
+	runIterTests(t, "IterNextC3", NFKC, iterTestsC, false)
+}
+
+type SegmentTest struct {
+	in  string
+	out []string
+}
+
+var segmentTests = []SegmentTest{
+	{rep('a', MaxSegmentSize), []string{rep('a', MaxSegmentSize), ""}},
+	{rep('a', MaxSegmentSize+2), []string{rep('a', MaxSegmentSize-1), "aaa", ""}},
+	{rep('a', MaxSegmentSize) + "\u0300aa", []string{rep('a', MaxSegmentSize-1), "a\u0300", "aa", ""}},
+}
+
+// Note that, by design, segmentation is equal for composing and decomposing forms.
+func TestIterSegmentation(t *testing.T) {
+	segmentTest(t, "SegmentTestD", NFD, segmentTests)
+	segmentTest(t, "SegmentTestC", NFC, segmentTests)
+}
+
+func segmentTest(t *testing.T, name string, f Form, tests []SegmentTest) {
+	iter := Iter{}
+	for i, tt := range segmentTests {
+		buf := make([]byte, MaxSegmentSize)
+		iter.SetInputString(f, tt.in)
+		for j, seg := range tt.out {
+			if seg == "" {
+				if !iter.Done() {
+					n := iter.Next(buf)
+					res := string(buf[:n])
+					t.Errorf(`%s:%d:%d: expected Done()==true, found segment "%s"`, name, i, j, res)
+				}
+				continue
+			}
+			if iter.Done() {
+				t.Errorf("%s:%d:%d: Done()==true, want false", name, i, j)
+			}
+			n := iter.Next(buf)
+			seg = f.String(seg)
+			if res := string(buf[:n]); res != seg {
+				t.Errorf(`%s:%d:%d" segment was "%s" (%d); want "%s" (%d)`, name, i, j, res, len(res), seg, len(seg))
+			}
+		}
+	}
+}
diff --git a/libgo/go/exp/norm/normalize.go b/libgo/go/exp/norm/normalize.go
index 030d900918e..b5cd44abfa0 100644
--- a/libgo/go/exp/norm/normalize.go
+++ b/libgo/go/exp/norm/normalize.go
@@ -243,7 +243,7 @@ func quickSpan(rb *reorderBuffer, i int) int {
 	lastSegStart := i
 	src, n := rb.src, rb.nsrc
 	for i < n {
-		if j := src.skipASCII(i); i != j {
+		if j := src.skipASCII(i, n); i != j {
 			i = j
 			lastSegStart = i - 1
 			lastCC = 0
@@ -448,11 +448,16 @@ func decomposeToLastBoundary(rb *reorderBuffer, buf []byte) []byte {
 		}
 		// Check that decomposition doesn't result in overflow.
 		if info.hasDecomposition() {
-			dcomp := info.decomposition()
-			for i := 0; i < len(dcomp); {
-				inf := rb.f.info(inputBytes(dcomp), i)
-				i += int(inf.size)
+			if isHangul(buf) {
+				i += int(info.size)
 				n++
+			} else {
+				dcomp := info.decomposition()
+				for i := 0; i < len(dcomp); {
+					inf := rb.f.info(inputBytes(dcomp), i)
+					i += int(inf.size)
+					n++
+				}
 			}
 		} else {
 			n++
diff --git a/libgo/go/exp/norm/normalize_test.go b/libgo/go/exp/norm/normalize_test.go
index c7d5e08fca0..8b970598b4d 100644
--- a/libgo/go/exp/norm/normalize_test.go
+++ b/libgo/go/exp/norm/normalize_test.go
@@ -5,6 +5,7 @@
 package norm
 
 import (
+	"bytes"
 	"strings"
 	"testing"
 )
@@ -495,15 +496,40 @@ func TestAppend(t *testing.T) {
 	runAppendTests(t, "TestString", NFKC, stringF, appendTests)
 }
 
+func appendBench(f Form, in []byte) func() {
+	buf := make([]byte, 0, 4*len(in))
+	return func() {
+		f.Append(buf, in...)
+	}
+}
+
+func iterBench(f Form, in []byte) func() {
+	buf := make([]byte, 4*len(in))
+	iter := Iter{}
+	return func() {
+		iter.SetInput(f, in)
+		for !iter.Done() {
+			iter.Next(buf)
+		}
+	}
+}
+
+func appendBenchmarks(bm []func(), f Form, in []byte) []func() {
+	//bm = append(bm, appendBench(f, in))
+	bm = append(bm, iterBench(f, in))
+	return bm
+}
+
 func doFormBenchmark(b *testing.B, inf, f Form, s string) {
 	b.StopTimer()
 	in := inf.Bytes([]byte(s))
-	buf := make([]byte, 2*len(in))
-	b.SetBytes(int64(len(in)))
+	bm := appendBenchmarks(nil, f, in)
+	b.SetBytes(int64(len(in) * len(bm)))
 	b.StartTimer()
 	for i := 0; i < b.N; i++ {
-		buf = f.Append(buf[0:0], in...)
-		buf = buf[0:0]
+		for _, fn := range bm {
+			fn()
+		}
 	}
 }
 
@@ -549,17 +575,21 @@ func BenchmarkNormalizeHangulNFD2NFD(b *testing.B) {
 	doFormBenchmark(b, NFD, NFD, txt_kr)
 }
 
+var forms = []Form{NFC, NFD, NFKC, NFKD}
+
 func doTextBenchmark(b *testing.B, s string) {
 	b.StopTimer()
-	b.SetBytes(int64(len(s)) * 4)
 	in := []byte(s)
-	var buf = make([]byte, 0, 2*len(in))
+	bm := []func(){}
+	for _, f := range forms {
+		bm = appendBenchmarks(bm, f, in)
+	}
+	b.SetBytes(int64(len(s) * len(bm)))
 	b.StartTimer()
 	for i := 0; i < b.N; i++ {
-		NFC.Append(buf, in...)
-		NFD.Append(buf, in...)
-		NFKC.Append(buf, in...)
-		NFKD.Append(buf, in...)
+		for _, f := range bm {
+			f()
+		}
 	}
 }
 
@@ -584,6 +614,11 @@ func BenchmarkJapanese(b *testing.B) {
 func BenchmarkChinese(b *testing.B) {
 	doTextBenchmark(b, txt_cn)
 }
+func BenchmarkOverflow(b *testing.B) {
+	doTextBenchmark(b, overflow)
+}
+
+var overflow = string(bytes.Repeat([]byte("\u035D"), 4096)) + "\u035B"
 
 // Tests sampled from the Canonical ordering tests (Part 2) of
 // http://unicode.org/Public/UNIDATA/NormalizationTest.txt
diff --git a/libgo/go/exp/norm/normregtest.go b/libgo/go/exp/norm/normregtest.go
index c2ab25bc99d..507de1ae834 100644
--- a/libgo/go/exp/norm/normregtest.go
+++ b/libgo/go/exp/norm/normregtest.go
@@ -220,6 +220,17 @@ func cmpIsNormal(t *Test, name string, f norm.Form, test string, result, want bo
 func doTest(t *Test, f norm.Form, gold, test string) {
 	result := f.Bytes([]byte(test))
 	cmpResult(t, "Bytes", f, gold, test, string(result))
+	sresult := f.String(test)
+	cmpResult(t, "String", f, gold, test, sresult)
+	buf := make([]byte, norm.MaxSegmentSize)
+	acc := []byte{}
+	i := norm.Iter{}
+	i.SetInputString(f, test)
+	for !i.Done() {
+		n := i.Next(buf)
+		acc = append(acc, buf[:n]...)
+	}
+	cmpResult(t, "Iter.Next", f, gold, test, string(acc))
 	for i := range test {
 		out := f.Append(f.Bytes([]byte(test[:i])), []byte(test[i:])...)
 		cmpResult(t, fmt.Sprintf(":Append:%d", i), f, gold, test, string(out))
diff --git a/libgo/go/exp/proxy/socks5.go b/libgo/go/exp/proxy/socks5.go
index 466e135eb10..62fa5c9296d 100644
--- a/libgo/go/exp/proxy/socks5.go
+++ b/libgo/go/exp/proxy/socks5.go
@@ -98,9 +98,9 @@ func (s *socks5) Dial(network, addr string) (net.Conn, error) {
 
 	buf = append(buf, socks5Version)
 	if len(s.user) > 0 && len(s.user) < 256 && len(s.password) < 256 {
-		buf = append(buf, 2, /* num auth methods */ socks5AuthNone, socks5AuthPassword)
+		buf = append(buf, 2 /* num auth methods */, socks5AuthNone, socks5AuthPassword)
 	} else {
-		buf = append(buf, 1, /* num auth methods */ socks5AuthNone)
+		buf = append(buf, 1 /* num auth methods */, socks5AuthNone)
 	}
 
 	if _, err = conn.Write(buf); err != nil {
@@ -139,7 +139,7 @@ func (s *socks5) Dial(network, addr string) (net.Conn, error) {
 	}
 
 	buf = buf[:0]
-	buf = append(buf, socks5Version, socks5Connect, 0 /* reserved */ )
+	buf = append(buf, socks5Version, socks5Connect, 0 /* reserved */)
 
 	if ip := net.ParseIP(host); ip != nil {
 		if len(ip) == 4 {
diff --git a/libgo/go/exp/terminal/terminal.go b/libgo/go/exp/terminal/terminal.go
index c3ba5bde2ee..c1ed0c0c443 100644
--- a/libgo/go/exp/terminal/terminal.go
+++ b/libgo/go/exp/terminal/terminal.go
@@ -389,12 +389,12 @@ func (t *Terminal) Write(buf []byte) (n int, err error) {
 
 	// We have a prompt and possibly user input on the screen. We
 	// have to clear it first.
-	t.move(0, /* up */ 0, /* down */ t.cursorX, /* left */ 0 /* right */ )
+	t.move(0 /* up */, 0 /* down */, t.cursorX /* left */, 0 /* right */)
 	t.cursorX = 0
 	t.clearLineToRight()
 
 	for t.cursorY > 0 {
-		t.move(1, /* up */ 0, 0, 0)
+		t.move(1 /* up */, 0, 0, 0)
 		t.cursorY--
 		t.clearLineToRight()
 	}
diff --git a/libgo/go/exp/winfsnotify/winfsnotify_test.go b/libgo/go/exp/winfsnotify/winfsnotify_test.go
index 59ac1624a26..4a1929a8397 100644
--- a/libgo/go/exp/winfsnotify/winfsnotify_test.go
+++ b/libgo/go/exp/winfsnotify/winfsnotify_test.go
@@ -7,6 +7,7 @@
 package winfsnotify
 
 import (
+	"io/ioutil"
 	"os"
 	"testing"
 	"time"
@@ -115,7 +116,13 @@ func TestNotifyClose(t *testing.T) {
 		t.Fatal("double Close() test failed: second Close() call didn't return")
 	}
 
-	err := watcher.Watch("_test")
+	dir, err := ioutil.TempDir("", "wininotify")
+	if err != nil {
+		t.Fatalf("TempDir failed: %s", err)
+	}
+	defer os.RemoveAll(dir)
+
+	err = watcher.Watch(dir)
 	if err == nil {
 		t.Fatal("expected error on Watch() after Close(), got nil")
 	}
diff --git a/libgo/go/go/doc/example.go b/libgo/go/go/doc/example.go
index 1c23b0d95c3..a7e0e250a2e 100644
--- a/libgo/go/go/doc/example.go
+++ b/libgo/go/go/doc/example.go
@@ -2,28 +2,31 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// Extract example functions from package ASTs.
+// Extract example functions from file ASTs.
 
 package doc
 
 import (
 	"go/ast"
-	"go/printer"
 	"go/token"
+	"regexp"
+	"sort"
 	"strings"
 	"unicode"
 	"unicode/utf8"
 )
 
 type Example struct {
-	Name   string                 // name of the item being demonstrated
-	Body   *printer.CommentedNode // code
-	Output string                 // expected output
+	Name     string // name of the item being exemplified
+	Doc      string // example function doc string
+	Code     ast.Node
+	Comments []*ast.CommentGroup
+	Output   string // expected output
 }
 
-func Examples(pkg *ast.Package) []*Example {
+func Examples(files ...*ast.File) []*Example {
 	var list []*Example
-	for _, file := range pkg.Files {
+	for _, file := range files {
 		hasTests := false // file contains tests or benchmarks
 		numDecl := 0      // number of non-import declarations in the file
 		var flist []*Example
@@ -45,26 +48,54 @@ func Examples(pkg *ast.Package) []*Example {
 			if !isTest(name, "Example") {
 				continue
 			}
+			var doc string
+			if f.Doc != nil {
+				doc = f.Doc.Text()
+			}
 			flist = append(flist, &Example{
-				Name: name[len("Example"):],
-				Body: &printer.CommentedNode{
-					Node:     f.Body,
-					Comments: file.Comments,
-				},
-				Output: f.Doc.Text(),
+				Name:     name[len("Example"):],
+				Doc:      doc,
+				Code:     f.Body,
+				Comments: file.Comments,
+				Output:   exampleOutput(f, file.Comments),
 			})
 		}
 		if !hasTests && numDecl > 1 && len(flist) == 1 {
 			// If this file only has one example function, some
 			// other top-level declarations, and no tests or
 			// benchmarks, use the whole file as the example.
-			flist[0].Body.Node = file
+			flist[0].Code = file
 		}
 		list = append(list, flist...)
 	}
+	sort.Sort(exampleByName(list))
 	return list
 }
 
+var outputPrefix = regexp.MustCompile(`(?i)^[[:space:]]*output:`)
+
+func exampleOutput(fun *ast.FuncDecl, comments []*ast.CommentGroup) string {
+	// find the last comment in the function
+	var last *ast.CommentGroup
+	for _, cg := range comments {
+		if cg.Pos() < fun.Pos() {
+			continue
+		}
+		if cg.End() > fun.End() {
+			break
+		}
+		last = cg
+	}
+	if last != nil {
+		// test that it begins with the correct prefix
+		text := last.Text()
+		if loc := outputPrefix.FindStringIndex(text); loc != nil {
+			return strings.TrimSpace(text[loc[1]:])
+		}
+	}
+	return "" // no suitable comment found
+}
+
 // isTest tells whether name looks like a test, example, or benchmark.
 // It is a Test (say) if there is a character after Test that is not a
 // lower-case letter. (We don't want Testiness.)
@@ -78,3 +109,9 @@ func isTest(name, prefix string) bool {
 	rune, _ := utf8.DecodeRuneInString(name[len(prefix):])
 	return !unicode.IsLower(rune)
 }
+
+type exampleByName []*Example
+
+func (s exampleByName) Len() int           { return len(s) }
+func (s exampleByName) Swap(i, j int)      { s[i], s[j] = s[j], s[i] }
+func (s exampleByName) Less(i, j int) bool { return s[i].Name < s[j].Name }
diff --git a/libgo/go/go/doc/reader.go b/libgo/go/go/doc/reader.go
index bdfb294adb0..3558892ebd0 100644
--- a/libgo/go/go/doc/reader.go
+++ b/libgo/go/go/doc/reader.go
@@ -439,8 +439,10 @@ func (r *reader) readFile(src *ast.File) {
 						// gets to (re-)use the declaration documentation
 						// if there's none associated with the spec itself
 						fake := &ast.GenDecl{
-							d.Doc, d.Pos(), token.TYPE, token.NoPos,
-							[]ast.Spec{s}, token.NoPos,
+							Doc:    d.Doc,
+							TokPos: d.Pos(),
+							Tok:    token.TYPE,
+							Specs:  []ast.Spec{s},
 						}
 						r.readType(fake, s)
 					}
@@ -460,7 +462,7 @@ func (r *reader) readFile(src *ast.File) {
 				// non-empty BUG comment; collect comment without BUG prefix
 				list := append([]*ast.Comment(nil), c.List...) // make a copy
 				list[0].Text = text[m[1]:]
-				r.bugs = append(r.bugs, (&ast.CommentGroup{list}).Text())
+				r.bugs = append(r.bugs, (&ast.CommentGroup{List: list}).Text())
 			}
 		}
 	}
@@ -530,7 +532,7 @@ func customizeRecv(f *Func, recvTypeName string, embeddedIsPtr bool, level int)
 	_, origRecvIsPtr := newField.Type.(*ast.StarExpr)
 	var typ ast.Expr = ast.NewIdent(recvTypeName)
 	if !embeddedIsPtr && origRecvIsPtr {
-		typ = &ast.StarExpr{token.NoPos, typ}
+		typ = &ast.StarExpr{X: typ}
 	}
 	newField.Type = typ
 
diff --git a/libgo/go/go/doc/synopsis.go b/libgo/go/go/doc/synopsis.go
new file mode 100644
index 00000000000..2192d78c0cd
--- /dev/null
+++ b/libgo/go/go/doc/synopsis.go
@@ -0,0 +1,52 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package doc
+
+import "unicode"
+
+// firstSentenceLen returns the length of the first sentence in s.
+// The sentence ends after the first period followed by space and
+// not preceded by exactly one uppercase letter.
+//
+func firstSentenceLen(s string) int {
+	var ppp, pp, p rune
+	for i, q := range s {
+		if q == '\n' || q == '\r' || q == '\t' {
+			q = ' '
+		}
+		if q == ' ' && p == '.' && (!unicode.IsUpper(pp) || unicode.IsUpper(ppp)) {
+			return i
+		}
+		ppp, pp, p = pp, p, q
+	}
+	return len(s)
+}
+
+// Synopsis returns a cleaned version of the first sentence in s.
+// That sentence ends after the first period followed by space and
+// not preceded by exactly one uppercase letter. The result string
+// has no \n, \r, or \t characters and uses only single spaces between
+// words.
+//
+func Synopsis(s string) string {
+	n := firstSentenceLen(s)
+	var b []byte
+	p := byte(' ')
+	for i := 0; i < n; i++ {
+		q := s[i]
+		if q == '\n' || q == '\r' || q == '\t' {
+			q = ' '
+		}
+		if q != ' ' || p != ' ' {
+			b = append(b, q)
+			p = q
+		}
+	}
+	// remove trailing blank, if any
+	if n := len(b); n > 0 && p == ' ' {
+		b = b[0 : n-1]
+	}
+	return string(b)
+}
diff --git a/libgo/go/go/doc/synopsis_test.go b/libgo/go/go/doc/synopsis_test.go
new file mode 100644
index 00000000000..dfc6598af47
--- /dev/null
+++ b/libgo/go/go/doc/synopsis_test.go
@@ -0,0 +1,44 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package doc
+
+import "testing"
+
+var tests = []struct {
+	txt string
+	fsl int
+	syn string
+}{
+	{"", 0, ""},
+	{"foo", 3, "foo"},
+	{"foo.", 4, "foo."},
+	{"foo.bar", 7, "foo.bar"},
+	{"  foo.  ", 6, "foo."},
+	{"  foo\t  bar.\n", 12, "foo bar."},
+	{"  foo\t  bar.\n", 12, "foo bar."},
+	{"a  b\n\nc\r\rd\t\t", 12, "a b c d"},
+	{"a  b\n\nc\r\rd\t\t  . BLA", 15, "a b c d ."},
+	{"Package poems by T.S.Eliot. To rhyme...", 27, "Package poems by T.S.Eliot."},
+	{"Package poems by T. S. Eliot. To rhyme...", 29, "Package poems by T. S. Eliot."},
+	{"foo implements the foo ABI. The foo ABI is...", 27, "foo implements the foo ABI."},
+	{"Package\nfoo. ..", 12, "Package foo."},
+	{"P . Q.", 3, "P ."},
+	{"P. Q.   ", 8, "P. Q."},
+	{"Package Καλημέρα κόσμε.", 36, "Package Καλημέρα κόσμε."},
+	{"Package こんにちは 世界\n", 31, "Package こんにちは 世界"},
+}
+
+func TestSynopsis(t *testing.T) {
+	for _, e := range tests {
+		fsl := firstSentenceLen(e.txt)
+		if fsl != e.fsl {
+			t.Errorf("got fsl = %d; want %d for %q\n", fsl, e.fsl, e.txt)
+		}
+		syn := Synopsis(e.txt)
+		if syn != e.syn {
+			t.Errorf("got syn = %q; want %q for %q\n", syn, e.syn, e.txt)
+		}
+	}
+}
diff --git a/libgo/go/go/doc/testdata/benchmark.go b/libgo/go/go/doc/testdata/benchmark.go
index 0bf567b7c4d..0aded5bb4c7 100644
--- a/libgo/go/go/doc/testdata/benchmark.go
+++ b/libgo/go/go/doc/testdata/benchmark.go
@@ -16,7 +16,7 @@ var matchBenchmarks = flag.String("test.bench", "", "regular expression to selec
 var benchTime = flag.Float64("test.benchtime", 1, "approximate run time for each benchmark, in seconds")
 
 // An internal type but exported because it is cross-package; part of the implementation
-// of gotest.
+// of go test.
 type InternalBenchmark struct {
 	Name string
 	F    func(b *B)
@@ -213,7 +213,7 @@ func (r BenchmarkResult) String() string {
 }
 
 // An internal function but exported because it is cross-package; part of the implementation
-// of gotest.
+// of go test.
 func RunBenchmarks(matchString func(pat, str string) (bool, error), benchmarks []InternalBenchmark) {
 	// If no flag was specified, don't run benchmarks.
 	if len(*matchBenchmarks) == 0 {
@@ -281,7 +281,7 @@ func (b *B) trimOutput() {
 }
 
 // Benchmark benchmarks a single function. Useful for creating
-// custom benchmarks that do not use gotest.
+// custom benchmarks that do not use go test.
 func Benchmark(f func(b *B)) BenchmarkResult {
 	b := &B{
 		common: common{
diff --git a/libgo/go/go/doc/testdata/testing.1.golden b/libgo/go/go/doc/testdata/testing.1.golden
index 1f92f8fe3e1..d26a4685ca0 100644
--- a/libgo/go/go/doc/testdata/testing.1.golden
+++ b/libgo/go/go/doc/testdata/testing.1.golden
@@ -27,7 +27,7 @@ VARIABLES
 		// The short flag requests that tests run more quickly, but its functionality
 		// is provided by test writers themselves.  The testing package is just its
 		// home.  The all.bash installation script sets it to make installation more
-		// efficient, but by default the flag is off so a plain "gotest" will do a
+		// efficient, but by default the flag is off so a plain "go test" will do a
 		// full test of the package.
 		short	= flag.Bool("test.short", false, "run smaller test suite to save time")
 	
diff --git a/libgo/go/go/doc/testdata/testing.go b/libgo/go/go/doc/testdata/testing.go
index cfe212dc1d7..71c1d1eaf0e 100644
--- a/libgo/go/go/doc/testdata/testing.go
+++ b/libgo/go/go/doc/testdata/testing.go
@@ -3,7 +3,7 @@
 // license that can be found in the LICENSE file.
 
 // Package testing provides support for automated testing of Go packages.
-// It is intended to be used in concert with the ``gotest'' utility, which automates
+// It is intended to be used in concert with the ``go test'' utility, which automates
 // execution of any function of the form
 //     func TestXxx(*testing.T)
 // where Xxx can be any alphanumeric string (but the first letter must not be in
@@ -12,7 +12,7 @@
 //
 // Functions of the form
 //     func BenchmarkXxx(*testing.B)
-// are considered benchmarks, and are executed by gotest when the -test.bench
+// are considered benchmarks, and are executed by go test when the -test.bench
 // flag is provided.
 //
 // A sample benchmark function looks like this:
@@ -53,7 +53,7 @@ var (
 	// The short flag requests that tests run more quickly, but its functionality
 	// is provided by test writers themselves.  The testing package is just its
 	// home.  The all.bash installation script sets it to make installation more
-	// efficient, but by default the flag is off so a plain "gotest" will do a
+	// efficient, but by default the flag is off so a plain "go test" will do a
 	// full test of the package.
 	short = flag.Bool("test.short", false, "run smaller test suite to save time")
 
@@ -205,7 +205,7 @@ func (t *T) Parallel() {
 }
 
 // An internal type but exported because it is cross-package; part of the implementation
-// of gotest.
+// of go test.
 type InternalTest struct {
 	Name string
 	F    func(*T)
@@ -227,7 +227,7 @@ func tRunner(t *T, test *InternalTest) {
 }
 
 // An internal function but exported because it is cross-package; part of the implementation
-// of gotest.
+// of go test.
 func Main(matchString func(pat, str string) (bool, error), tests []InternalTest, benchmarks []InternalBenchmark, examples []InternalExample) {
 	flag.Parse()
 	parseCpuList()
diff --git a/libgo/go/go/parser/parser.go b/libgo/go/go/parser/parser.go
index 6a0b61eb48c..c1e61904486 100644
--- a/libgo/go/go/parser/parser.go
+++ b/libgo/go/go/parser/parser.go
@@ -249,7 +249,7 @@ func (p *parser) consumeComment() (comment *ast.Comment, endline int) {
 		}
 	}
 
-	comment = &ast.Comment{p.pos, p.lit}
+	comment = &ast.Comment{Slash: p.pos, Text: p.lit}
 	p.next0()
 
 	return
@@ -270,7 +270,7 @@ func (p *parser) consumeCommentGroup() (comments *ast.CommentGroup, endline int)
 	}
 
 	// add comment group to the comments list
-	comments = &ast.CommentGroup{list}
+	comments = &ast.CommentGroup{List: list}
 	p.comments = append(p.comments, comments)
 
 	return
@@ -391,7 +391,7 @@ func (p *parser) parseIdent() *ast.Ident {
 	} else {
 		p.expect(token.IDENT) // use expect() error handling
 	}
-	return &ast.Ident{pos, name, nil}
+	return &ast.Ident{NamePos: pos, Name: name}
 }
 
 func (p *parser) parseIdentList() (list []*ast.Ident) {
@@ -469,7 +469,7 @@ func (p *parser) parseType() ast.Expr {
 		pos := p.pos
 		p.errorExpected(pos, "type")
 		p.next() // make progress
-		return &ast.BadExpr{pos, p.pos}
+		return &ast.BadExpr{From: pos, To: p.pos}
 	}
 
 	return typ
@@ -489,7 +489,7 @@ func (p *parser) parseTypeName() ast.Expr {
 		p.next()
 		p.resolve(ident)
 		sel := p.parseIdent()
-		return &ast.SelectorExpr{ident, sel}
+		return &ast.SelectorExpr{X: ident, Sel: sel}
 	}
 
 	return ident
@@ -503,7 +503,7 @@ func (p *parser) parseArrayType(ellipsisOk bool) ast.Expr {
 	lbrack := p.expect(token.LBRACK)
 	var len ast.Expr
 	if ellipsisOk && p.tok == token.ELLIPSIS {
-		len = &ast.Ellipsis{p.pos, nil}
+		len = &ast.Ellipsis{Ellipsis: p.pos}
 		p.next()
 	} else if p.tok != token.RBRACK {
 		len = p.parseRhs()
@@ -511,7 +511,7 @@ func (p *parser) parseArrayType(ellipsisOk bool) ast.Expr {
 	p.expect(token.RBRACK)
 	elt := p.parseType()
 
-	return &ast.ArrayType{lbrack, len, elt}
+	return &ast.ArrayType{Lbrack: lbrack, Len: len, Elt: elt}
 }
 
 func (p *parser) makeIdentList(list []ast.Expr) []*ast.Ident {
@@ -521,7 +521,7 @@ func (p *parser) makeIdentList(list []ast.Expr) []*ast.Ident {
 		if !isIdent {
 			pos := x.Pos()
 			p.errorExpected(pos, "identifier")
-			ident = &ast.Ident{pos, "_", nil}
+			ident = &ast.Ident{NamePos: pos, Name: "_"}
 		}
 		idents[i] = ident
 	}
@@ -541,7 +541,7 @@ func (p *parser) parseFieldDecl(scope *ast.Scope) *ast.Field {
 	// optional tag
 	var tag *ast.BasicLit
 	if p.tok == token.STRING {
-		tag = &ast.BasicLit{p.pos, p.tok, p.lit}
+		tag = &ast.BasicLit{ValuePos: p.pos, Kind: p.tok, Value: p.lit}
 		p.next()
 	}
 
@@ -557,13 +557,13 @@ func (p *parser) parseFieldDecl(scope *ast.Scope) *ast.Field {
 		if n := len(list); n > 1 || !isTypeName(deref(typ)) {
 			pos := typ.Pos()
 			p.errorExpected(pos, "anonymous field")
-			typ = &ast.BadExpr{pos, list[n-1].End()}
+			typ = &ast.BadExpr{From: pos, To: list[n-1].End()}
 		}
 	}
 
 	p.expectSemi() // call before accessing p.linecomment
 
-	field := &ast.Field{doc, idents, typ, tag, p.lineComment}
+	field := &ast.Field{Doc: doc, Names: idents, Type: typ, Tag: tag, Comment: p.lineComment}
 	p.declare(field, nil, scope, ast.Var, idents...)
 
 	return field
@@ -586,7 +586,14 @@ func (p *parser) parseStructType() *ast.StructType {
 	}
 	rbrace := p.expect(token.RBRACE)
 
-	return &ast.StructType{pos, &ast.FieldList{lbrace, list, rbrace}, false}
+	return &ast.StructType{
+		Struct: pos,
+		Fields: &ast.FieldList{
+			Opening: lbrace,
+			List:    list,
+			Closing: rbrace,
+		},
+	}
 }
 
 func (p *parser) parsePointerType() *ast.StarExpr {
@@ -597,7 +604,7 @@ func (p *parser) parsePointerType() *ast.StarExpr {
 	star := p.expect(token.MUL)
 	base := p.parseType()
 
-	return &ast.StarExpr{star, base}
+	return &ast.StarExpr{Star: star, X: base}
 }
 
 func (p *parser) tryVarType(isParam bool) ast.Expr {
@@ -607,9 +614,9 @@ func (p *parser) tryVarType(isParam bool) ast.Expr {
 		typ := p.tryIdentOrType(isParam) // don't use parseType so we can provide better error message
 		if typ == nil {
 			p.error(pos, "'...' parameter is missing type")
-			typ = &ast.BadExpr{pos, p.pos}
+			typ = &ast.BadExpr{From: pos, To: p.pos}
 		}
-		return &ast.Ellipsis{pos, typ}
+		return &ast.Ellipsis{Ellipsis: pos, Elt: typ}
 	}
 	return p.tryIdentOrType(false)
 }
@@ -620,7 +627,7 @@ func (p *parser) parseVarType(isParam bool) ast.Expr {
 		pos := p.pos
 		p.errorExpected(pos, "type")
 		p.next() // make progress
-		typ = &ast.BadExpr{pos, p.pos}
+		typ = &ast.BadExpr{From: pos, To: p.pos}
 	}
 	return typ
 }
@@ -661,7 +668,7 @@ func (p *parser) parseParameterList(scope *ast.Scope, ellipsisOk bool) (params [
 	if typ != nil {
 		// IdentifierList Type
 		idents := p.makeIdentList(list)
-		field := &ast.Field{nil, idents, typ, nil, nil}
+		field := &ast.Field{Names: idents, Type: typ}
 		params = append(params, field)
 		// Go spec: The scope of an identifier denoting a function
 		// parameter or result variable is the function body.
@@ -673,7 +680,7 @@ func (p *parser) parseParameterList(scope *ast.Scope, ellipsisOk bool) (params [
 		for p.tok != token.RPAREN && p.tok != token.EOF {
 			idents := p.parseIdentList()
 			typ := p.parseVarType(ellipsisOk)
-			field := &ast.Field{nil, idents, typ, nil, nil}
+			field := &ast.Field{Names: idents, Type: typ}
 			params = append(params, field)
 			// Go spec: The scope of an identifier denoting a function
 			// parameter or result variable is the function body.
@@ -708,7 +715,7 @@ func (p *parser) parseParameters(scope *ast.Scope, ellipsisOk bool) *ast.FieldLi
 	}
 	rparen := p.expect(token.RPAREN)
 
-	return &ast.FieldList{lparen, params, rparen}
+	return &ast.FieldList{Opening: lparen, List: params, Closing: rparen}
 }
 
 func (p *parser) parseResult(scope *ast.Scope) *ast.FieldList {
@@ -750,7 +757,7 @@ func (p *parser) parseFuncType() (*ast.FuncType, *ast.Scope) {
 	scope := ast.NewScope(p.topScope) // function scope
 	params, results := p.parseSignature(scope)
 
-	return &ast.FuncType{pos, params, results}, scope
+	return &ast.FuncType{Func: pos, Params: params, Results: results}, scope
 }
 
 func (p *parser) parseMethodSpec(scope *ast.Scope) *ast.Field {
@@ -767,7 +774,7 @@ func (p *parser) parseMethodSpec(scope *ast.Scope) *ast.Field {
 		idents = []*ast.Ident{ident}
 		scope := ast.NewScope(nil) // method scope
 		params, results := p.parseSignature(scope)
-		typ = &ast.FuncType{token.NoPos, params, results}
+		typ = &ast.FuncType{Func: token.NoPos, Params: params, Results: results}
 	} else {
 		// embedded interface
 		typ = x
@@ -775,7 +782,7 @@ func (p *parser) parseMethodSpec(scope *ast.Scope) *ast.Field {
 	}
 	p.expectSemi() // call before accessing p.linecomment
 
-	spec := &ast.Field{doc, idents, typ, nil, p.lineComment}
+	spec := &ast.Field{Doc: doc, Names: idents, Type: typ, Comment: p.lineComment}
 	p.declare(spec, nil, scope, ast.Fun, idents...)
 
 	return spec
@@ -795,7 +802,14 @@ func (p *parser) parseInterfaceType() *ast.InterfaceType {
 	}
 	rbrace := p.expect(token.RBRACE)
 
-	return &ast.InterfaceType{pos, &ast.FieldList{lbrace, list, rbrace}, false}
+	return &ast.InterfaceType{
+		Interface: pos,
+		Methods: &ast.FieldList{
+			Opening: lbrace,
+			List:    list,
+			Closing: rbrace,
+		},
+	}
 }
 
 func (p *parser) parseMapType() *ast.MapType {
@@ -809,7 +823,7 @@ func (p *parser) parseMapType() *ast.MapType {
 	p.expect(token.RBRACK)
 	value := p.parseType()
 
-	return &ast.MapType{pos, key, value}
+	return &ast.MapType{Map: pos, Key: key, Value: value}
 }
 
 func (p *parser) parseChanType() *ast.ChanType {
@@ -832,7 +846,7 @@ func (p *parser) parseChanType() *ast.ChanType {
 	}
 	value := p.parseType()
 
-	return &ast.ChanType{pos, dir, value}
+	return &ast.ChanType{Begin: pos, Dir: dir, Value: value}
 }
 
 // If the result is an identifier, it is not resolved.
@@ -860,7 +874,7 @@ func (p *parser) tryIdentOrType(ellipsisOk bool) ast.Expr {
 		p.next()
 		typ := p.parseType()
 		rparen := p.expect(token.RPAREN)
-		return &ast.ParenExpr{lparen, typ, rparen}
+		return &ast.ParenExpr{Lparen: lparen, X: typ, Rparen: rparen}
 	}
 
 	// no type found
@@ -903,7 +917,7 @@ func (p *parser) parseBody(scope *ast.Scope) *ast.BlockStmt {
 	p.closeScope()
 	rbrace := p.expect(token.RBRACE)
 
-	return &ast.BlockStmt{lbrace, list, rbrace}
+	return &ast.BlockStmt{Lbrace: lbrace, List: list, Rbrace: rbrace}
 }
 
 func (p *parser) parseBlockStmt() *ast.BlockStmt {
@@ -917,7 +931,7 @@ func (p *parser) parseBlockStmt() *ast.BlockStmt {
 	p.closeScope()
 	rbrace := p.expect(token.RBRACE)
 
-	return &ast.BlockStmt{lbrace, list, rbrace}
+	return &ast.BlockStmt{Lbrace: lbrace, List: list, Rbrace: rbrace}
 }
 
 // ----------------------------------------------------------------------------
@@ -938,7 +952,7 @@ func (p *parser) parseFuncTypeOrLit() ast.Expr {
 	body := p.parseBody(scope)
 	p.exprLev--
 
-	return &ast.FuncLit{typ, body}
+	return &ast.FuncLit{Type: typ, Body: body}
 }
 
 // parseOperand may return an expression or a raw type (incl. array
@@ -959,7 +973,7 @@ func (p *parser) parseOperand(lhs bool) ast.Expr {
 		return x
 
 	case token.INT, token.FLOAT, token.IMAG, token.CHAR, token.STRING:
-		x := &ast.BasicLit{p.pos, p.tok, p.lit}
+		x := &ast.BasicLit{ValuePos: p.pos, Kind: p.tok, Value: p.lit}
 		p.next()
 		return x
 
@@ -970,7 +984,7 @@ func (p *parser) parseOperand(lhs bool) ast.Expr {
 		x := p.parseRhsOrType() // types may be parenthesized: (some type)
 		p.exprLev--
 		rparen := p.expect(token.RPAREN)
-		return &ast.ParenExpr{lparen, x, rparen}
+		return &ast.ParenExpr{Lparen: lparen, X: x, Rparen: rparen}
 
 	case token.FUNC:
 		return p.parseFuncTypeOrLit()
@@ -987,7 +1001,7 @@ func (p *parser) parseOperand(lhs bool) ast.Expr {
 	pos := p.pos
 	p.errorExpected(pos, "operand")
 	p.next() // make progress
-	return &ast.BadExpr{pos, p.pos}
+	return &ast.BadExpr{From: pos, To: p.pos}
 }
 
 func (p *parser) parseSelector(x ast.Expr) ast.Expr {
@@ -997,7 +1011,7 @@ func (p *parser) parseSelector(x ast.Expr) ast.Expr {
 
 	sel := p.parseIdent()
 
-	return &ast.SelectorExpr{x, sel}
+	return &ast.SelectorExpr{X: x, Sel: sel}
 }
 
 func (p *parser) parseTypeAssertion(x ast.Expr) ast.Expr {
@@ -1015,7 +1029,7 @@ func (p *parser) parseTypeAssertion(x ast.Expr) ast.Expr {
 	}
 	p.expect(token.RPAREN)
 
-	return &ast.TypeAssertExpr{x, typ}
+	return &ast.TypeAssertExpr{X: x, Type: typ}
 }
 
 func (p *parser) parseIndexOrSlice(x ast.Expr) ast.Expr {
@@ -1041,9 +1055,9 @@ func (p *parser) parseIndexOrSlice(x ast.Expr) ast.Expr {
 	rbrack := p.expect(token.RBRACK)
 
 	if isSlice {
-		return &ast.SliceExpr{x, lbrack, low, high, rbrack}
+		return &ast.SliceExpr{X: x, Lbrack: lbrack, Low: low, High: high, Rbrack: rbrack}
 	}
-	return &ast.IndexExpr{x, lbrack, low, rbrack}
+	return &ast.IndexExpr{X: x, Lbrack: lbrack, Index: low, Rbrack: rbrack}
 }
 
 func (p *parser) parseCallOrConversion(fun ast.Expr) *ast.CallExpr {
@@ -1069,7 +1083,7 @@ func (p *parser) parseCallOrConversion(fun ast.Expr) *ast.CallExpr {
 	p.exprLev--
 	rparen := p.expectClosing(token.RPAREN, "argument list")
 
-	return &ast.CallExpr{fun, lparen, list, ellipsis, rparen}
+	return &ast.CallExpr{Fun: fun, Lparen: lparen, Args: list, Ellipsis: ellipsis, Rparen: rparen}
 }
 
 func (p *parser) parseElement(keyOk bool) ast.Expr {
@@ -1086,7 +1100,7 @@ func (p *parser) parseElement(keyOk bool) ast.Expr {
 		if p.tok == token.COLON {
 			colon := p.pos
 			p.next()
-			return &ast.KeyValueExpr{x, colon, p.parseElement(false)}
+			return &ast.KeyValueExpr{Key: x, Colon: colon, Value: p.parseElement(false)}
 		}
 		p.resolve(x) // not a map key
 	}
@@ -1123,7 +1137,7 @@ func (p *parser) parseLiteralValue(typ ast.Expr) ast.Expr {
 	}
 	p.exprLev--
 	rbrace := p.expectClosing(token.RBRACE, "composite literal")
-	return &ast.CompositeLit{typ, lbrace, elts, rbrace}
+	return &ast.CompositeLit{Type: typ, Lbrace: lbrace, Elts: elts, Rbrace: rbrace}
 }
 
 // checkExpr checks that x is an expression (and not a type).
@@ -1152,7 +1166,7 @@ func (p *parser) checkExpr(x ast.Expr) ast.Expr {
 	default:
 		// all other nodes are not proper expressions
 		p.errorExpected(x.Pos(), "expression")
-		x = &ast.BadExpr{x.Pos(), x.End()}
+		x = &ast.BadExpr{From: x.Pos(), To: x.End()}
 	}
 	return x
 }
@@ -1215,7 +1229,7 @@ func (p *parser) checkExprOrType(x ast.Expr) ast.Expr {
 	case *ast.ArrayType:
 		if len, isEllipsis := t.Len.(*ast.Ellipsis); isEllipsis {
 			p.error(len.Pos(), "expected array length, found '...'")
-			x = &ast.BadExpr{x.Pos(), x.End()}
+			x = &ast.BadExpr{From: x.Pos(), To: x.End()}
 		}
 	}
 
@@ -1247,7 +1261,7 @@ L:
 				pos := p.pos
 				p.next() // make progress
 				p.errorExpected(pos, "selector or type assertion")
-				x = &ast.BadExpr{pos, p.pos}
+				x = &ast.BadExpr{From: pos, To: p.pos}
 			}
 		case token.LBRACK:
 			if lhs {
@@ -1288,7 +1302,7 @@ func (p *parser) parseUnaryExpr(lhs bool) ast.Expr {
 		pos, op := p.pos, p.tok
 		p.next()
 		x := p.parseUnaryExpr(false)
-		return &ast.UnaryExpr{pos, op, p.checkExpr(x)}
+		return &ast.UnaryExpr{OpPos: pos, Op: op, X: p.checkExpr(x)}
 
 	case token.ARROW:
 		// channel type or receive expression
@@ -1297,18 +1311,18 @@ func (p *parser) parseUnaryExpr(lhs bool) ast.Expr {
 		if p.tok == token.CHAN {
 			p.next()
 			value := p.parseType()
-			return &ast.ChanType{pos, ast.RECV, value}
+			return &ast.ChanType{Begin: pos, Dir: ast.RECV, Value: value}
 		}
 
 		x := p.parseUnaryExpr(false)
-		return &ast.UnaryExpr{pos, token.ARROW, p.checkExpr(x)}
+		return &ast.UnaryExpr{OpPos: pos, Op: token.ARROW, X: p.checkExpr(x)}
 
 	case token.MUL:
 		// pointer type or unary "*" expression
 		pos := p.pos
 		p.next()
 		x := p.parseUnaryExpr(false)
-		return &ast.StarExpr{pos, p.checkExprOrType(x)}
+		return &ast.StarExpr{Star: pos, X: p.checkExprOrType(x)}
 	}
 
 	return p.parsePrimaryExpr(lhs)
@@ -1330,7 +1344,7 @@ func (p *parser) parseBinaryExpr(lhs bool, prec1 int) ast.Expr {
 				lhs = false
 			}
 			y := p.parseBinaryExpr(false, prec+1)
-			x = &ast.BinaryExpr{p.checkExpr(x), pos, op, p.checkExpr(y)}
+			x = &ast.BinaryExpr{X: p.checkExpr(x), OpPos: pos, Op: op, Y: p.checkExpr(y)}
 		}
 	}
 
@@ -1392,12 +1406,12 @@ func (p *parser) parseSimpleStmt(mode int) (ast.Stmt, bool) {
 		if mode == rangeOk && p.tok == token.RANGE && (tok == token.DEFINE || tok == token.ASSIGN) {
 			pos := p.pos
 			p.next()
-			y = []ast.Expr{&ast.UnaryExpr{pos, token.RANGE, p.parseRhs()}}
+			y = []ast.Expr{&ast.UnaryExpr{OpPos: pos, Op: token.RANGE, X: p.parseRhs()}}
 			isRange = true
 		} else {
 			y = p.parseRhsList()
 		}
-		as := &ast.AssignStmt{x, pos, tok, y}
+		as := &ast.AssignStmt{Lhs: x, TokPos: pos, Tok: tok, Rhs: y}
 		if tok == token.DEFINE {
 			p.shortVarDecl(as, x)
 		}
@@ -1418,7 +1432,7 @@ func (p *parser) parseSimpleStmt(mode int) (ast.Stmt, bool) {
 			// Go spec: The scope of a label is the body of the function
 			// in which it is declared and excludes the body of any nested
 			// function.
-			stmt := &ast.LabeledStmt{label, colon, p.parseStmt()}
+			stmt := &ast.LabeledStmt{Label: label, Colon: colon, Stmt: p.parseStmt()}
 			p.declare(stmt, nil, p.labelScope, ast.Lbl, label)
 			return stmt, false
 		}
@@ -1429,24 +1443,24 @@ func (p *parser) parseSimpleStmt(mode int) (ast.Stmt, bool) {
 		// before the ':' that caused the problem. Thus, use the (latest) colon
 		// position for error reporting.
 		p.error(colon, "illegal label declaration")
-		return &ast.BadStmt{x[0].Pos(), colon + 1}, false
+		return &ast.BadStmt{From: x[0].Pos(), To: colon + 1}, false
 
 	case token.ARROW:
 		// send statement
 		arrow := p.pos
 		p.next()
 		y := p.parseRhs()
-		return &ast.SendStmt{x[0], arrow, y}, false
+		return &ast.SendStmt{Chan: x[0], Arrow: arrow, Value: y}, false
 
 	case token.INC, token.DEC:
 		// increment or decrement
-		s := &ast.IncDecStmt{x[0], p.pos, p.tok}
+		s := &ast.IncDecStmt{X: x[0], TokPos: p.pos, Tok: p.tok}
 		p.next()
 		return s, false
 	}
 
 	// expression
-	return &ast.ExprStmt{x[0]}, false
+	return &ast.ExprStmt{X: x[0]}, false
 }
 
 func (p *parser) parseCallExpr() *ast.CallExpr {
@@ -1467,10 +1481,10 @@ func (p *parser) parseGoStmt() ast.Stmt {
 	call := p.parseCallExpr()
 	p.expectSemi()
 	if call == nil {
-		return &ast.BadStmt{pos, pos + 2} // len("go")
+		return &ast.BadStmt{From: pos, To: pos + 2} // len("go")
 	}
 
-	return &ast.GoStmt{pos, call}
+	return &ast.GoStmt{Go: pos, Call: call}
 }
 
 func (p *parser) parseDeferStmt() ast.Stmt {
@@ -1482,10 +1496,10 @@ func (p *parser) parseDeferStmt() ast.Stmt {
 	call := p.parseCallExpr()
 	p.expectSemi()
 	if call == nil {
-		return &ast.BadStmt{pos, pos + 5} // len("defer")
+		return &ast.BadStmt{From: pos, To: pos + 5} // len("defer")
 	}
 
-	return &ast.DeferStmt{pos, call}
+	return &ast.DeferStmt{Defer: pos, Call: call}
 }
 
 func (p *parser) parseReturnStmt() *ast.ReturnStmt {
@@ -1501,7 +1515,7 @@ func (p *parser) parseReturnStmt() *ast.ReturnStmt {
 	}
 	p.expectSemi()
 
-	return &ast.ReturnStmt{pos, x}
+	return &ast.ReturnStmt{Return: pos, Results: x}
 }
 
 func (p *parser) parseBranchStmt(tok token.Token) *ast.BranchStmt {
@@ -1519,7 +1533,7 @@ func (p *parser) parseBranchStmt(tok token.Token) *ast.BranchStmt {
 	}
 	p.expectSemi()
 
-	return &ast.BranchStmt{pos, tok, label}
+	return &ast.BranchStmt{TokPos: pos, Tok: tok, Label: label}
 }
 
 func (p *parser) makeExpr(s ast.Stmt) ast.Expr {
@@ -1530,7 +1544,7 @@ func (p *parser) makeExpr(s ast.Stmt) ast.Expr {
 		return p.checkExpr(es.X)
 	}
 	p.error(s.Pos(), "expected condition, found simple statement")
-	return &ast.BadExpr{s.Pos(), s.End()}
+	return &ast.BadExpr{From: s.Pos(), To: s.End()}
 }
 
 func (p *parser) parseIfStmt() *ast.IfStmt {
@@ -1572,7 +1586,7 @@ func (p *parser) parseIfStmt() *ast.IfStmt {
 		p.expectSemi()
 	}
 
-	return &ast.IfStmt{pos, s, x, body, else_}
+	return &ast.IfStmt{If: pos, Init: s, Cond: x, Body: body, Else: else_}
 }
 
 func (p *parser) parseTypeList() (list []ast.Expr) {
@@ -1612,7 +1626,7 @@ func (p *parser) parseCaseClause(typeSwitch bool) *ast.CaseClause {
 	body := p.parseStmtList()
 	p.closeScope()
 
-	return &ast.CaseClause{pos, list, colon, body}
+	return &ast.CaseClause{Case: pos, List: list, Colon: colon, Body: body}
 }
 
 func isTypeSwitchAssert(x ast.Expr) bool {
@@ -1681,13 +1695,13 @@ func (p *parser) parseSwitchStmt() ast.Stmt {
 	}
 	rbrace := p.expect(token.RBRACE)
 	p.expectSemi()
-	body := &ast.BlockStmt{lbrace, list, rbrace}
+	body := &ast.BlockStmt{Lbrace: lbrace, List: list, Rbrace: rbrace}
 
 	if typeSwitch {
-		return &ast.TypeSwitchStmt{pos, s1, s2, body}
+		return &ast.TypeSwitchStmt{Switch: pos, Init: s1, Assign: s2, Body: body}
 	}
 
-	return &ast.SwitchStmt{pos, s1, p.makeExpr(s2), body}
+	return &ast.SwitchStmt{Switch: pos, Init: s1, Tag: p.makeExpr(s2), Body: body}
 }
 
 func (p *parser) parseCommClause() *ast.CommClause {
@@ -1710,7 +1724,7 @@ func (p *parser) parseCommClause() *ast.CommClause {
 			arrow := p.pos
 			p.next()
 			rhs := p.parseRhs()
-			comm = &ast.SendStmt{lhs[0], arrow, rhs}
+			comm = &ast.SendStmt{Chan: lhs[0], Arrow: arrow, Value: rhs}
 		} else {
 			// RecvStmt
 			if tok := p.tok; tok == token.ASSIGN || tok == token.DEFINE {
@@ -1723,7 +1737,7 @@ func (p *parser) parseCommClause() *ast.CommClause {
 				pos := p.pos
 				p.next()
 				rhs := p.parseRhs()
-				as := &ast.AssignStmt{lhs, pos, tok, []ast.Expr{rhs}}
+				as := &ast.AssignStmt{Lhs: lhs, TokPos: pos, Tok: tok, Rhs: []ast.Expr{rhs}}
 				if tok == token.DEFINE {
 					p.shortVarDecl(as, lhs)
 				}
@@ -1734,7 +1748,7 @@ func (p *parser) parseCommClause() *ast.CommClause {
 					p.errorExpected(lhs[0].Pos(), "1 expression")
 					// continue with first expression
 				}
-				comm = &ast.ExprStmt{lhs[0]}
+				comm = &ast.ExprStmt{X: lhs[0]}
 			}
 		}
 	} else {
@@ -1745,7 +1759,7 @@ func (p *parser) parseCommClause() *ast.CommClause {
 	body := p.parseStmtList()
 	p.closeScope()
 
-	return &ast.CommClause{pos, comm, colon, body}
+	return &ast.CommClause{Case: pos, Comm: comm, Colon: colon, Body: body}
 }
 
 func (p *parser) parseSelectStmt() *ast.SelectStmt {
@@ -1761,9 +1775,9 @@ func (p *parser) parseSelectStmt() *ast.SelectStmt {
 	}
 	rbrace := p.expect(token.RBRACE)
 	p.expectSemi()
-	body := &ast.BlockStmt{lbrace, list, rbrace}
+	body := &ast.BlockStmt{Lbrace: lbrace, List: list, Rbrace: rbrace}
 
-	return &ast.SelectStmt{pos, body}
+	return &ast.SelectStmt{Select: pos, Body: body}
 }
 
 func (p *parser) parseForStmt() ast.Stmt {
@@ -1812,16 +1826,30 @@ func (p *parser) parseForStmt() ast.Stmt {
 			key = as.Lhs[0]
 		default:
 			p.errorExpected(as.Lhs[0].Pos(), "1 or 2 expressions")
-			return &ast.BadStmt{pos, body.End()}
+			return &ast.BadStmt{From: pos, To: body.End()}
 		}
 		// parseSimpleStmt returned a right-hand side that
 		// is a single unary expression of the form "range x"
 		x := as.Rhs[0].(*ast.UnaryExpr).X
-		return &ast.RangeStmt{pos, key, value, as.TokPos, as.Tok, x, body}
+		return &ast.RangeStmt{
+			For:    pos,
+			Key:    key,
+			Value:  value,
+			TokPos: as.TokPos,
+			Tok:    as.Tok,
+			X:      x,
+			Body:   body,
+		}
 	}
 
 	// regular for statement
-	return &ast.ForStmt{pos, s1, p.makeExpr(s2), s3, body}
+	return &ast.ForStmt{
+		For:  pos,
+		Init: s1,
+		Cond: p.makeExpr(s2),
+		Post: s3,
+		Body: body,
+	}
 }
 
 func (p *parser) parseStmt() (s ast.Stmt) {
@@ -1831,12 +1859,12 @@ func (p *parser) parseStmt() (s ast.Stmt) {
 
 	switch p.tok {
 	case token.CONST, token.TYPE, token.VAR:
-		s = &ast.DeclStmt{p.parseDecl()}
+		s = &ast.DeclStmt{Decl: p.parseDecl()}
 	case
-		// tokens that may start a top-level expression
-		token.IDENT, token.INT, token.FLOAT, token.CHAR, token.STRING, token.FUNC, token.LPAREN, // operand
-		token.LBRACK, token.STRUCT, // composite type
-		token.MUL, token.AND, token.ARROW, token.ADD, token.SUB, token.XOR: // unary operators
+		// tokens that may start an expression
+		token.IDENT, token.INT, token.FLOAT, token.IMAG, token.CHAR, token.STRING, token.FUNC, token.LPAREN, // operands
+		token.LBRACK, token.STRUCT, // composite types
+		token.ADD, token.SUB, token.MUL, token.AND, token.XOR, token.ARROW, token.NOT: // unary operators
 		s, _ = p.parseSimpleStmt(labelOk)
 		// because of the required look-ahead, labeled statements are
 		// parsed by parseSimpleStmt - don't expect a semicolon after
@@ -1864,17 +1892,17 @@ func (p *parser) parseStmt() (s ast.Stmt) {
 	case token.FOR:
 		s = p.parseForStmt()
 	case token.SEMICOLON:
-		s = &ast.EmptyStmt{p.pos}
+		s = &ast.EmptyStmt{Semicolon: p.pos}
 		p.next()
 	case token.RBRACE:
 		// a semicolon may be omitted before a closing "}"
-		s = &ast.EmptyStmt{p.pos}
+		s = &ast.EmptyStmt{Semicolon: p.pos}
 	default:
 		// no statement found
 		pos := p.pos
 		p.errorExpected(pos, "statement")
 		p.next() // make progress
-		s = &ast.BadStmt{pos, p.pos}
+		s = &ast.BadStmt{From: pos, To: p.pos}
 	}
 
 	return
@@ -1893,7 +1921,7 @@ func parseImportSpec(p *parser, doc *ast.CommentGroup, _ int) ast.Spec {
 	var ident *ast.Ident
 	switch p.tok {
 	case token.PERIOD:
-		ident = &ast.Ident{p.pos, ".", nil}
+		ident = &ast.Ident{NamePos: p.pos, Name: "."}
 		p.next()
 	case token.IDENT:
 		ident = p.parseIdent()
@@ -1901,7 +1929,7 @@ func parseImportSpec(p *parser, doc *ast.CommentGroup, _ int) ast.Spec {
 
 	var path *ast.BasicLit
 	if p.tok == token.STRING {
-		path = &ast.BasicLit{p.pos, p.tok, p.lit}
+		path = &ast.BasicLit{ValuePos: p.pos, Kind: p.tok, Value: p.lit}
 		p.next()
 	} else {
 		p.expect(token.STRING) // use expect() error handling
@@ -1909,7 +1937,12 @@ 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, token.NoPos}
+	spec := &ast.ImportSpec{
+		Doc:     doc,
+		Name:    ident,
+		Path:    path,
+		Comment: p.lineComment,
+	}
 	p.imports = append(p.imports, spec)
 
 	return spec
@@ -1933,7 +1966,13 @@ func parseConstSpec(p *parser, doc *ast.CommentGroup, iota int) ast.Spec {
 	// a function begins at the end of the ConstSpec or VarSpec and ends at
 	// the end of the innermost containing block.
 	// (Global identifiers are resolved in a separate phase after parsing.)
-	spec := &ast.ValueSpec{doc, idents, typ, values, p.lineComment}
+	spec := &ast.ValueSpec{
+		Doc:     doc,
+		Names:   idents,
+		Type:    typ,
+		Values:  values,
+		Comment: p.lineComment,
+	}
 	p.declare(spec, iota, p.topScope, ast.Con, idents...)
 
 	return spec
@@ -1950,7 +1989,7 @@ func parseTypeSpec(p *parser, doc *ast.CommentGroup, _ int) ast.Spec {
 	// at the identifier in the TypeSpec and ends at the end of the innermost
 	// containing block.
 	// (Global identifiers are resolved in a separate phase after parsing.)
-	spec := &ast.TypeSpec{doc, ident, nil, nil}
+	spec := &ast.TypeSpec{Doc: doc, Name: ident}
 	p.declare(spec, nil, p.topScope, ast.Typ, ident)
 
 	spec.Type = p.parseType()
@@ -1978,7 +2017,13 @@ func parseVarSpec(p *parser, doc *ast.CommentGroup, _ int) ast.Spec {
 	// a function begins at the end of the ConstSpec or VarSpec and ends at
 	// the end of the innermost containing block.
 	// (Global identifiers are resolved in a separate phase after parsing.)
-	spec := &ast.ValueSpec{doc, idents, typ, values, p.lineComment}
+	spec := &ast.ValueSpec{
+		Doc:     doc,
+		Names:   idents,
+		Type:    typ,
+		Values:  values,
+		Comment: p.lineComment,
+	}
 	p.declare(spec, nil, p.topScope, ast.Var, idents...)
 
 	return spec
@@ -2005,7 +2050,14 @@ func (p *parser) parseGenDecl(keyword token.Token, f parseSpecFunction) *ast.Gen
 		list = append(list, f(p, nil, 0))
 	}
 
-	return &ast.GenDecl{doc, pos, keyword, lparen, list, rparen}
+	return &ast.GenDecl{
+		Doc:    doc,
+		TokPos: pos,
+		Tok:    keyword,
+		Lparen: lparen,
+		Specs:  list,
+		Rparen: rparen,
+	}
 }
 
 func (p *parser) parseReceiver(scope *ast.Scope) *ast.FieldList {
@@ -2018,7 +2070,7 @@ func (p *parser) parseReceiver(scope *ast.Scope) *ast.FieldList {
 	// must have exactly one receiver
 	if par.NumFields() != 1 {
 		p.errorExpected(par.Opening, "exactly one receiver")
-		par.List = []*ast.Field{{Type: &ast.BadExpr{par.Opening, par.Closing + 1}}}
+		par.List = []*ast.Field{{Type: &ast.BadExpr{From: par.Opening, To: par.Closing + 1}}}
 		return par
 	}
 
@@ -2027,7 +2079,7 @@ func (p *parser) parseReceiver(scope *ast.Scope) *ast.FieldList {
 	base := deref(recv.Type)
 	if _, isIdent := base.(*ast.Ident); !isIdent {
 		p.errorExpected(base.Pos(), "(unqualified) identifier")
-		par.List = []*ast.Field{{Type: &ast.BadExpr{recv.Pos(), recv.End()}}}
+		par.List = []*ast.Field{{Type: &ast.BadExpr{From: recv.Pos(), To: recv.End()}}}
 	}
 
 	return par
@@ -2057,7 +2109,17 @@ func (p *parser) parseFuncDecl() *ast.FuncDecl {
 	}
 	p.expectSemi()
 
-	decl := &ast.FuncDecl{doc, recv, ident, &ast.FuncType{pos, params, results}, body}
+	decl := &ast.FuncDecl{
+		Doc:  doc,
+		Recv: recv,
+		Name: ident,
+		Type: &ast.FuncType{
+			Func:    pos,
+			Params:  params,
+			Results: results,
+		},
+		Body: body,
+	}
 	if recv == nil {
 		// Go spec: The scope of an identifier denoting a constant, type,
 		// variable, or function (but not method) declared at top level
@@ -2096,7 +2158,7 @@ func (p *parser) parseDecl() ast.Decl {
 		pos := p.pos
 		p.errorExpected(pos, "declaration")
 		p.next() // make progress
-		decl := &ast.BadDecl{pos, p.pos}
+		decl := &ast.BadDecl{From: pos, To: p.pos}
 		return decl
 	}
 
@@ -2155,5 +2217,14 @@ func (p *parser) parseFile() *ast.File {
 		}
 	}
 
-	return &ast.File{doc, pos, ident, decls, p.pkgScope, p.imports, p.unresolved[0:i], p.comments}
+	return &ast.File{
+		Doc:        doc,
+		Package:    pos,
+		Name:       ident,
+		Decls:      decls,
+		Scope:      p.pkgScope,
+		Imports:    p.imports,
+		Unresolved: p.unresolved[0:i],
+		Comments:   p.comments,
+	}
 }
diff --git a/libgo/go/go/printer/nodes.go b/libgo/go/go/printer/nodes.go
index 25935fb42bb..cd5e075c16c 100644
--- a/libgo/go/go/printer/nodes.go
+++ b/libgo/go/go/printer/nodes.go
@@ -87,7 +87,6 @@ const (
 	commaSep                            // elements are separated by commas
 	commaTerm                           // list is optionally terminated by a comma
 	noIndent                            // no extra indentation in multi-line lists
-	periodSep                           // elements are separated by periods
 )
 
 // Sets multiLine to true if the identifier list spans multiple lines.
@@ -133,7 +132,9 @@ func (p *printer) exprList(prev0 token.Pos, list []ast.Expr, depth int, mode exp
 		for i, x := range list {
 			if i > 0 {
 				if mode&commaSep != 0 {
-					p.print(token.COMMA)
+					// use position of expression following the comma as
+					// comma position for correct comment placement
+					p.print(x.Pos(), token.COMMA)
 				}
 				p.print(blank)
 			}
@@ -213,14 +214,18 @@ func (p *printer) exprList(prev0 token.Pos, list []ast.Expr, depth int, mode exp
 		}
 
 		if i > 0 {
-			switch {
-			case mode&commaSep != 0:
+			needsLinebreak := prevLine < line && prevLine > 0 && line > 0
+			if mode&commaSep != 0 {
+				// use position of expression following the comma as
+				// comma position for correct comment placement, but
+				// only if the expression is on the same line
+				if !needsLinebreak {
+					p.print(x.Pos())
+				}
 				p.print(token.COMMA)
-			case mode&periodSep != 0:
-				p.print(token.PERIOD)
 			}
-			needsBlank := mode&periodSep == 0 // period-separated list elements don't need a blank
-			if prevLine < line && prevLine > 0 && line > 0 {
+			needsBlank := true
+			if needsLinebreak {
 				// lines are broken using newlines so comments remain aligned
 				// unless forceFF is set or there are multiple expressions on
 				// the same line in which case formfeed is used
@@ -287,11 +292,18 @@ func (p *printer) parameters(fields *ast.FieldList, multiLine *bool) {
 				parLineBeg = parLineEnd
 			}
 			// separating "," if needed
+			needsLinebreak := 0 < prevLine && prevLine < parLineBeg
 			if i > 0 {
+				// use position of parameter following the comma as
+				// comma position for correct comma placement, but
+				// only if the next parameter is on the same line
+				if !needsLinebreak {
+					p.print(par.Pos())
+				}
 				p.print(token.COMMA)
 			}
 			// separator if needed (linebreak or blank)
-			if 0 < prevLine && prevLine < parLineBeg && p.linebreak(parLineBeg, 0, ws, true) {
+			if needsLinebreak && p.linebreak(parLineBeg, 0, ws, true) {
 				// break line if the opening "(" or previous parameter ended on a different line
 				ws = ignore
 				*multiLine = true
@@ -316,7 +328,7 @@ func (p *printer) parameters(fields *ast.FieldList, multiLine *bool) {
 		// if the closing ")" is on a separate line from the last parameter,
 		// print an additional "," and line break
 		if closing := p.lineFor(fields.Closing); 0 < prevLine && prevLine < closing {
-			p.print(",")
+			p.print(token.COMMA)
 			p.linebreak(closing, 0, ignore, true)
 		}
 		// unindent if we indented
@@ -374,7 +386,7 @@ func (p *printer) isOneLineFieldList(list []*ast.Field) bool {
 }
 
 func (p *printer) setLineComment(text string) {
-	p.setComment(&ast.CommentGroup{[]*ast.Comment{{token.NoPos, text}}})
+	p.setComment(&ast.CommentGroup{List: []*ast.Comment{{Slash: token.NoPos, Text: text}}})
 }
 
 func (p *printer) fieldList(fields *ast.FieldList, isStruct, isIncomplete bool) {
@@ -397,6 +409,7 @@ func (p *printer) fieldList(fields *ast.FieldList, isStruct, isIncomplete bool)
 			f := list[0]
 			for i, x := range f.Names {
 				if i > 0 {
+					// no comments so no need for comma position
 					p.print(token.COMMA, blank)
 				}
 				p.expr(x, ignoreMultiLine)
@@ -668,63 +681,6 @@ func isBinary(expr ast.Expr) bool {
 	return ok
 }
 
-// If the expression contains one or more selector expressions, splits it into
-// two expressions at the rightmost period. Writes entire expr to suffix when
-// selector isn't found. Rewrites AST nodes for calls, index expressions and
-// type assertions, all of which may be found in selector chains, to make them
-// parts of the chain.
-func splitSelector(expr ast.Expr) (body, suffix ast.Expr) {
-	switch x := expr.(type) {
-	case *ast.SelectorExpr:
-		body, suffix = x.X, x.Sel
-		return
-	case *ast.CallExpr:
-		body, suffix = splitSelector(x.Fun)
-		if body != nil {
-			suffix = &ast.CallExpr{suffix, x.Lparen, x.Args, x.Ellipsis, x.Rparen}
-			return
-		}
-	case *ast.IndexExpr:
-		body, suffix = splitSelector(x.X)
-		if body != nil {
-			suffix = &ast.IndexExpr{suffix, x.Lbrack, x.Index, x.Rbrack}
-			return
-		}
-	case *ast.SliceExpr:
-		body, suffix = splitSelector(x.X)
-		if body != nil {
-			suffix = &ast.SliceExpr{suffix, x.Lbrack, x.Low, x.High, x.Rbrack}
-			return
-		}
-	case *ast.TypeAssertExpr:
-		body, suffix = splitSelector(x.X)
-		if body != nil {
-			suffix = &ast.TypeAssertExpr{suffix, x.Type}
-			return
-		}
-	}
-	suffix = expr
-	return
-}
-
-// Convert an expression into an expression list split at the periods of
-// selector expressions.
-func selectorExprList(expr ast.Expr) (list []ast.Expr) {
-	// split expression
-	for expr != nil {
-		var suffix ast.Expr
-		expr, suffix = splitSelector(expr)
-		list = append(list, suffix)
-	}
-
-	// reverse list
-	for i, j := 0, len(list)-1; i < j; i, j = i+1, j-1 {
-		list[i], list[j] = list[j], list[i]
-	}
-
-	return
-}
-
 // Sets multiLine to true if the expression spans multiple lines.
 func (p *printer) expr1(expr ast.Expr, prec1, depth int, multiLine *bool) {
 	p.print(expr.Pos())
@@ -798,8 +754,14 @@ func (p *printer) expr1(expr ast.Expr, prec1, depth int, multiLine *bool) {
 		}
 
 	case *ast.SelectorExpr:
-		parts := selectorExprList(expr)
-		p.exprList(token.NoPos, parts, depth, periodSep, multiLine, token.NoPos)
+		p.expr1(x.X, token.HighestPrec, depth, multiLine)
+		p.print(token.PERIOD)
+		if line := p.lineFor(x.Sel.Pos()); p.pos.IsValid() && p.pos.Line < line {
+			p.print(indent, newline, x.Sel.Pos(), x.Sel, unindent)
+			*multiLine = true
+		} else {
+			p.print(x.Sel.Pos(), x.Sel)
+		}
 
 	case *ast.TypeAssertExpr:
 		p.expr1(x.X, token.HighestPrec, depth, multiLine)
@@ -1180,7 +1142,9 @@ func (p *printer) stmt(stmt ast.Stmt, nextIsRBrace bool, multiLine *bool) {
 		p.print(token.FOR, blank)
 		p.expr(s.Key, multiLine)
 		if s.Value != nil {
-			p.print(token.COMMA, blank)
+			// use position of value following the comma as
+			// comma position for correct comment placement
+			p.print(s.Value.Pos(), token.COMMA, blank)
 			p.expr(s.Value, multiLine)
 		}
 		p.print(blank, s.TokPos, s.Tok, blank, token.RANGE, blank)
diff --git a/libgo/go/go/printer/printer.go b/libgo/go/go/printer/printer.go
index c9949205e8a..72f65a1d852 100644
--- a/libgo/go/go/printer/printer.go
+++ b/libgo/go/go/printer/printer.go
@@ -686,9 +686,11 @@ func (p *printer) intersperseComments(next token.Position, tok token.Token) (wro
 	}
 
 	if last != nil {
-		if last.Text[1] == '*' && p.lineFor(last.Pos()) == next.Line {
-			// the last comment is a /*-style comment and the next item
-			// follows on the same line: separate with an extra blank
+		// if the last comment is a /*-style comment and the next item
+		// follows on the same line but is not a comma or a "closing"
+		// token, add an extra blank for separation
+		if last.Text[1] == '*' && p.lineFor(last.Pos()) == next.Line && tok != token.COMMA &&
+			tok != token.RPAREN && tok != token.RBRACK && tok != token.RBRACE {
 			p.writeByte(' ', 1)
 		}
 		// ensure that there is a line break after a //-style comment,
diff --git a/libgo/go/go/printer/printer_test.go b/libgo/go/go/printer/printer_test.go
index fa133cd35f0..2d4f61356c1 100644
--- a/libgo/go/go/printer/printer_test.go
+++ b/libgo/go/go/printer/printer_test.go
@@ -283,10 +283,10 @@ func fibo(n int) {
 		t.Error("expected offset 1") // error in test
 	}
 
-	testComment(t, f, len(src), &ast.Comment{pos, "//-style comment"})
-	testComment(t, f, len(src), &ast.Comment{pos, "/*-style comment */"})
-	testComment(t, f, len(src), &ast.Comment{pos, "/*-style \n comment */"})
-	testComment(t, f, len(src), &ast.Comment{pos, "/*-style comment \n\n\n */"})
+	testComment(t, f, len(src), &ast.Comment{Slash: pos, Text: "//-style comment"})
+	testComment(t, f, len(src), &ast.Comment{Slash: pos, Text: "/*-style comment */"})
+	testComment(t, f, len(src), &ast.Comment{Slash: pos, Text: "/*-style \n comment */"})
+	testComment(t, f, len(src), &ast.Comment{Slash: pos, Text: "/*-style comment \n\n\n */"})
 }
 
 type visitor chan *ast.Ident
diff --git a/libgo/go/go/printer/testdata/comments.golden b/libgo/go/go/printer/testdata/comments.golden
index e5826eecefe..4c6f1ab8274 100644
--- a/libgo/go/go/printer/testdata/comments.golden
+++ b/libgo/go/go/printer/testdata/comments.golden
@@ -405,16 +405,17 @@ func _() {
 }
 
 // Some interesting interspersed comments.
+// See below for more common cases.
 func _( /* this */ x /* is */ /* an */ int) {
 }
 
-func _( /* no params */ )	{}
+func _( /* no params */)	{}
 
 func _() {
-	f( /* no args */ )
+	f( /* no args */)
 }
 
-func ( /* comment1 */ T /* comment2 */ ) _()	{}
+func ( /* comment1 */ T /* comment2 */) _()	{}
 
 func _() { /* one-line functions with comments are formatted as multi-line functions */
 }
@@ -425,7 +426,7 @@ func _() {
 }
 
 func _() {
-	_ = []int{0, 1 /* don't introduce a newline after this comment - was issue 1365 */ }
+	_ = []int{0, 1 /* don't introduce a newline after this comment - was issue 1365 */}
 }
 
 // Test cases from issue 1542:
@@ -448,8 +449,9 @@ func _() {
 	_ = a
 }
 
-// Comments immediately adjacent to punctuation (for which the go/printer
-// may only have estimated position information) must remain after the punctuation.
+// Comments immediately adjacent to punctuation followed by a newline
+// remain after the punctuation (looks better and permits alignment of
+// comments).
 func _() {
 	_ = T{
 		1,	// comment after comma
@@ -479,6 +481,35 @@ func _() {
 	}
 }
 
+// If there is no newline following punctuation, commas move before the punctuation.
+// This way, commas interspersed in lists stay with the respective expression.
+func f(x /* comment */, y int, z int /* comment */, u, v, w int /* comment */) {
+	f(x /* comment */, y)
+	f(x,	/* comment */
+		y)
+	f(
+		x,	/* comment */
+	)
+}
+
+func g(
+	x int,	/* comment */
+) {
+}
+
+type _ struct {
+	a, b /* comment */, c int
+}
+
+type _ struct {
+	a, b /* comment */, c int
+}
+
+func _() {
+	for a /* comment */, b := range x {
+	}
+}
+
 // Print line directives correctly.
 
 // The following is a legal line directive.
diff --git a/libgo/go/go/printer/testdata/comments.input b/libgo/go/go/printer/testdata/comments.input
index 55f6b61f21f..c0f8cca3a92 100644
--- a/libgo/go/go/printer/testdata/comments.input
+++ b/libgo/go/go/printer/testdata/comments.input
@@ -411,6 +411,7 @@ func _() {
 
 
 // Some interesting interspersed comments.
+// See below for more common cases.
 func _(/* this */x/* is *//* an */ int) {
 }
 
@@ -453,8 +454,9 @@ func _() {
 	_ = a
 }
 
-// Comments immediately adjacent to punctuation (for which the go/printer
-// may only have estimated position information) must remain after the punctuation.
+// Comments immediately adjacent to punctuation followed by a newline
+// remain after the punctuation (looks better and permits alignment of
+// comments).
 func _() {
 	_ = T{
 		1,    // comment after comma
@@ -486,6 +488,31 @@ func _() {
 	}
 }
 
+// If there is no newline following punctuation, commas move before the punctuation.
+// This way, commas interspersed in lists stay with the respective expression.
+func f(x/* comment */, y int, z int /* comment */, u, v, w int /* comment */) {
+	f(x /* comment */, y)
+	f(x /* comment */, 
+	y)
+	f(
+		x /* comment */,
+	)
+}
+
+func g(
+	x int /* comment */,
+) {}
+
+type _ struct {
+	a, b /* comment */, c int
+}
+
+type _ struct { a, b /* comment */, c int }
+
+func _() {
+	for a /* comment */, b := range x {
+	}
+}
 
 // Print line directives correctly.
 
diff --git a/libgo/go/go/printer/testdata/expressions.golden b/libgo/go/go/printer/testdata/expressions.golden
index d0cf24ad6f6..95fdd95ffbb 100644
--- a/libgo/go/go/printer/testdata/expressions.golden
+++ b/libgo/go/go/printer/testdata/expressions.golden
@@ -545,7 +545,7 @@ func _() {
 	// handle multiline argument list correctly
 	_ = new(T).
 		foo(
-			1).
+		1).
 		foo(2)
 
 	_ = new(T).foo(
@@ -587,12 +587,12 @@ func _() {
 	_ = new(T).
 		Field.
 		Array[3+
-			4].
+		4].
 		Table["foo"].
 		Blob.(*Type).
 		Slices[1:4].
 		Method(1, 2,
-			3).
+		3).
 		Thingy
 
 	_ = a.b.c
diff --git a/libgo/go/go/printer/testdata/expressions.raw b/libgo/go/go/printer/testdata/expressions.raw
index d7819a3baad..3442ba9b950 100644
--- a/libgo/go/go/printer/testdata/expressions.raw
+++ b/libgo/go/go/printer/testdata/expressions.raw
@@ -545,7 +545,7 @@ func _() {
 	// handle multiline argument list correctly
 	_ = new(T).
 		foo(
-			1).
+		1).
 		foo(2)
 
 	_ = new(T).foo(
@@ -587,12 +587,12 @@ func _() {
 	_ = new(T).
 		Field.
 		Array[3+
-			4].
+		4].
 		Table["foo"].
 		Blob.(*Type).
 		Slices[1:4].
 		Method(1, 2,
-			3).
+		3).
 		Thingy
 
 	_ = a.b.c
diff --git a/libgo/go/go/scanner/scanner.go b/libgo/go/go/scanner/scanner.go
index 458e1f9f37a..2395363b0ec 100644
--- a/libgo/go/go/scanner/scanner.go
+++ b/libgo/go/go/scanner/scanner.go
@@ -2,21 +2,9 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// Package scanner implements a scanner for Go source text. Takes a []byte as
-// source which can then be tokenized through repeated calls to the Scan
-// function. Typical use:
-//
-//	var s scanner.Scanner
-//	fset := token.NewFileSet()  // position information is relative to fset
-//	file := fset.AddFile(filename, fset.Base(), len(src))  // register file
-//	s.Init(file, src, nil /* no error handler */, 0)
-//	for {
-//		pos, tok, lit := s.Scan()
-//		if tok == token.EOF {
-//			break
-//		}
-//		// do something here with pos, tok, and lit
-//	}
+// Package scanner implements a scanner for Go source text.
+// It takes a []byte as source which can then be tokenized
+// through repeated calls to the Scan method.
 //
 package scanner
 
diff --git a/libgo/go/html/template/clone.go b/libgo/go/html/template/clone.go
deleted file mode 100644
index d0d8ea46733..00000000000
--- a/libgo/go/html/template/clone.go
+++ /dev/null
@@ -1,90 +0,0 @@
-// 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.
-
-package template
-
-import (
-	"text/template/parse"
-)
-
-// clone clones a template Node.
-func clone(n parse.Node) parse.Node {
-	switch t := n.(type) {
-	case *parse.ActionNode:
-		return cloneAction(t)
-	case *parse.IfNode:
-		b := new(parse.IfNode)
-		copyBranch(&b.BranchNode, &t.BranchNode)
-		return b
-	case *parse.ListNode:
-		return cloneList(t)
-	case *parse.RangeNode:
-		b := new(parse.RangeNode)
-		copyBranch(&b.BranchNode, &t.BranchNode)
-		return b
-	case *parse.TemplateNode:
-		return cloneTemplate(t)
-	case *parse.TextNode:
-		return cloneText(t)
-	case *parse.WithNode:
-		b := new(parse.WithNode)
-		copyBranch(&b.BranchNode, &t.BranchNode)
-		return b
-	}
-	panic("cloning " + n.String() + " is unimplemented")
-}
-
-// cloneAction returns a deep clone of n.
-func cloneAction(n *parse.ActionNode) *parse.ActionNode {
-	// We use keyless fields because they won't compile if a field is added.
-	return &parse.ActionNode{n.NodeType, n.Line, clonePipe(n.Pipe)}
-}
-
-// cloneList returns a deep clone of n.
-func cloneList(n *parse.ListNode) *parse.ListNode {
-	if n == nil {
-		return nil
-	}
-	// We use keyless fields because they won't compile if a field is added.
-	c := parse.ListNode{n.NodeType, make([]parse.Node, len(n.Nodes))}
-	for i, child := range n.Nodes {
-		c.Nodes[i] = clone(child)
-	}
-	return &c
-}
-
-// clonePipe returns a shallow clone of n.
-// The escaper does not modify pipe descendants in place so there's no need to
-// clone deeply.
-func clonePipe(n *parse.PipeNode) *parse.PipeNode {
-	if n == nil {
-		return nil
-	}
-	// We use keyless fields because they won't compile if a field is added.
-	return &parse.PipeNode{n.NodeType, n.Line, n.Decl, n.Cmds}
-}
-
-// cloneTemplate returns a deep clone of n.
-func cloneTemplate(n *parse.TemplateNode) *parse.TemplateNode {
-	// We use keyless fields because they won't compile if a field is added.
-	return &parse.TemplateNode{n.NodeType, n.Line, n.Name, clonePipe(n.Pipe)}
-}
-
-// cloneText clones the given node sharing its []byte.
-func cloneText(n *parse.TextNode) *parse.TextNode {
-	// We use keyless fields because they won't compile if a field is added.
-	return &parse.TextNode{n.NodeType, n.Text}
-}
-
-// copyBranch clones src into dst.
-func copyBranch(dst, src *parse.BranchNode) {
-	// We use keyless fields because they won't compile if a field is added.
-	*dst = parse.BranchNode{
-		src.NodeType,
-		src.Line,
-		clonePipe(src.Pipe),
-		cloneList(src.List),
-		cloneList(src.ElseList),
-	}
-}
diff --git a/libgo/go/html/template/clone_test.go b/libgo/go/html/template/clone_test.go
index 39788173b99..c612775d4f0 100644
--- a/libgo/go/html/template/clone_test.go
+++ b/libgo/go/html/template/clone_test.go
@@ -7,86 +7,109 @@ package template
 import (
 	"bytes"
 	"testing"
+	"text/template/parse"
 )
 
+func TestAddParseTree(t *testing.T) {
+	root := Must(New("root").Parse(`{{define "a"}} {{.}} {{template "b"}} {{.}} "></a>{{end}}`))
+	tree, err := parse.Parse("t", `{{define "b"}}<a href="{{end}}`, "", "", nil, nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	added := Must(root.AddParseTree("b", tree["b"]))
+	b := new(bytes.Buffer)
+	err = added.ExecuteTemplate(b, "a", "1>0")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if got, want := b.String(), ` 1&gt;0 <a href=" 1%3e0 "></a>`; got != want {
+		t.Errorf("got %q want %q", got, want)
+	}
+}
+
 func TestClone(t *testing.T) {
-	tests := []struct {
-		input, want, wantClone string
-	}{
-		{
-			`Hello, {{if true}}{{"<World>"}}{{end}}!`,
-			"Hello, <World>!",
-			"Hello, &lt;World&gt;!",
-		},
-		{
-			`Hello, {{if false}}{{.X}}{{else}}{{"<World>"}}{{end}}!`,
-			"Hello, <World>!",
-			"Hello, &lt;World&gt;!",
-		},
-		{
-			`Hello, {{with "<World>"}}{{.}}{{end}}!`,
-			"Hello, <World>!",
-			"Hello, &lt;World&gt;!",
-		},
-		{
-			`{{range .}}<p>{{.}}</p>{{end}}`,
-			"<p>foo</p><p><bar></p><p>baz</p>",
-			"<p>foo</p><p>&lt;bar&gt;</p><p>baz</p>",
-		},
-		{
-			`Hello, {{"<World>" | html}}!`,
-			"Hello, &lt;World&gt;!",
-			"Hello, &lt;World&gt;!",
-		},
-		{
-			`Hello{{if 1}}, World{{else}}{{template "d"}}{{end}}!`,
-			"Hello, World!",
-			"Hello, World!",
-		},
+	// The {{.}} will be executed with data "<i>*/" in different contexts.
+	// In the t0 template, it will be in a text context.
+	// In the t1 template, it will be in a URL context.
+	// In the t2 template, it will be in a JavaScript context.
+	// In the t3 template, it will be in a CSS context.
+	const tmpl = `{{define "a"}}{{template "lhs"}}{{.}}{{template "rhs"}}{{end}}`
+	b := new(bytes.Buffer)
+
+	// Create an incomplete template t0.
+	t0 := Must(New("t0").Parse(tmpl))
+
+	// Clone t0 as t1.
+	t1 := Must(t0.Clone())
+	Must(t1.Parse(`{{define "lhs"}} <a href=" {{end}}`))
+	Must(t1.Parse(`{{define "rhs"}} "></a> {{end}}`))
+
+	// Execute t1.
+	b.Reset()
+	if err := t1.ExecuteTemplate(b, "a", "<i>*/"); err != nil {
+		t.Fatal(err)
+	}
+	if got, want := b.String(), ` <a href=" %3ci%3e*/ "></a> `; got != want {
+		t.Errorf("t1: got %q want %q", got, want)
+	}
+
+	// Clone t0 as t2.
+	t2 := Must(t0.Clone())
+	Must(t2.Parse(`{{define "lhs"}} <p onclick="javascript: {{end}}`))
+	Must(t2.Parse(`{{define "rhs"}} "></p> {{end}}`))
+
+	// Execute t2.
+	b.Reset()
+	if err := t2.ExecuteTemplate(b, "a", "<i>*/"); err != nil {
+		t.Fatal(err)
+	}
+	if got, want := b.String(), ` <p onclick="javascript: &#34;\u003ci\u003e*/&#34; "></p> `; got != want {
+		t.Errorf("t2: got %q want %q", got, want)
 	}
 
-	for _, test := range tests {
-		s, err := New("s").Parse(test.input)
-		if err != nil {
-			t.Errorf("input=%q: unexpected parse error %v", test.input, err)
-		}
-
-		d, _ := New("d").Parse(test.input)
-		// Hack: just replace the root of the tree.
-		d.text.Root = cloneList(s.text.Root)
-
-		if want, got := s.text.Root.String(), d.text.Root.String(); want != got {
-			t.Errorf("want %q, got %q", want, got)
-		}
-
-		err = escapeTemplates(d, "d")
-		if err != nil {
-			t.Errorf("%q: failed to escape: %s", test.input, err)
-			continue
-		}
-
-		if want, got := "s", s.Name(); want != got {
-			t.Errorf("want %q, got %q", want, got)
-			continue
-		}
-		if want, got := "d", d.Name(); want != got {
-			t.Errorf("want %q, got %q", want, got)
-			continue
-		}
-
-		data := []string{"foo", "<bar>", "baz"}
-
-		var b bytes.Buffer
-		d.Execute(&b, data)
-		if got := b.String(); got != test.wantClone {
-			t.Errorf("input=%q: want %q, got %q", test.input, test.wantClone, got)
-		}
-
-		// Make sure escaping d did not affect s.
-		b.Reset()
-		s.text.Execute(&b, data)
-		if got := b.String(); got != test.want {
-			t.Errorf("input=%q: want %q, got %q", test.input, test.want, got)
-		}
+	// Clone t0 as t3, but do not execute t3 yet.
+	t3 := Must(t0.Clone())
+	Must(t3.Parse(`{{define "lhs"}} <style> {{end}}`))
+	Must(t3.Parse(`{{define "rhs"}} </style> {{end}}`))
+
+	// Complete t0.
+	Must(t0.Parse(`{{define "lhs"}} ( {{end}}`))
+	Must(t0.Parse(`{{define "rhs"}} ) {{end}}`))
+
+	// Clone t0 as t4. Redefining the "lhs" template should fail.
+	t4 := Must(t0.Clone())
+	if _, err := t4.Parse(`{{define "lhs"}} FAIL {{end}}`); err == nil {
+		t.Error(`redefine "lhs": got nil err want non-nil`)
+	}
+
+	// Execute t0.
+	b.Reset()
+	if err := t0.ExecuteTemplate(b, "a", "<i>*/"); err != nil {
+		t.Fatal(err)
+	}
+	if got, want := b.String(), ` ( &lt;i&gt;*/ ) `; got != want {
+		t.Errorf("t0: got %q want %q", got, want)
+	}
+
+	// Clone t0. This should fail, as t0 has already executed.
+	if _, err := t0.Clone(); err == nil {
+		t.Error(`t0.Clone(): got nil err want non-nil`)
+	}
+
+	// Similarly, cloning sub-templates should fail.
+	if _, err := t0.Lookup("a").Clone(); err == nil {
+		t.Error(`t0.Lookup("a").Clone(): got nil err want non-nil`)
+	}
+	if _, err := t0.Lookup("lhs").Clone(); err == nil {
+		t.Error(`t0.Lookup("lhs").Clone(): got nil err want non-nil`)
+	}
+
+	// Execute t3.
+	b.Reset()
+	if err := t3.ExecuteTemplate(b, "a", "<i>*/"); err != nil {
+		t.Fatal(err)
+	}
+	if got, want := b.String(), ` <style> ZgotmplZ </style> `; got != want {
+		t.Errorf("t3: got %q want %q", got, want)
 	}
 }
diff --git a/libgo/go/html/template/content.go b/libgo/go/html/template/content.go
index 4de7ccde912..539664f9729 100644
--- a/libgo/go/html/template/content.go
+++ b/libgo/go/html/template/content.go
@@ -85,6 +85,22 @@ func indirect(a interface{}) interface{} {
 	return v.Interface()
 }
 
+var (
+	errorType       = reflect.TypeOf((*error)(nil)).Elem()
+	fmtStringerType = reflect.TypeOf((*fmt.Stringer)(nil)).Elem()
+)
+
+// indirectToStringerOrError returns the value, after dereferencing as many times
+// as necessary to reach the base type (or nil) or an implementation of fmt.Stringer
+// or error,
+func indirectToStringerOrError(a interface{}) interface{} {
+	v := reflect.ValueOf(a)
+	for !v.Type().Implements(fmtStringerType) && !v.Type().Implements(errorType) && v.Kind() == reflect.Ptr && !v.IsNil() {
+		v = v.Elem()
+	}
+	return v.Interface()
+}
+
 // stringify converts its arguments to a string and the type of the content.
 // All pointers are dereferenced, as in the text/template package.
 func stringify(args ...interface{}) (string, contentType) {
@@ -107,7 +123,7 @@ func stringify(args ...interface{}) (string, contentType) {
 		}
 	}
 	for i, arg := range args {
-		args[i] = indirect(arg)
+		args[i] = indirectToStringerOrError(arg)
 	}
 	return fmt.Sprint(args...), contentTypePlain
 }
diff --git a/libgo/go/html/template/content_test.go b/libgo/go/html/template/content_test.go
index c96a521a59c..3c32e5e89cf 100644
--- a/libgo/go/html/template/content_test.go
+++ b/libgo/go/html/template/content_test.go
@@ -6,6 +6,7 @@ package template
 
 import (
 	"bytes"
+	"fmt"
 	"strings"
 	"testing"
 )
@@ -219,3 +220,42 @@ func TestTypedContent(t *testing.T) {
 		}
 	}
 }
+
+// Test that we print using the String method. Was issue 3073.
+type stringer struct {
+	v int
+}
+
+func (s *stringer) String() string {
+	return fmt.Sprintf("string=%d", s.v)
+}
+
+type errorer struct {
+	v int
+}
+
+func (s *errorer) Error() string {
+	return fmt.Sprintf("error=%d", s.v)
+}
+
+func TestStringer(t *testing.T) {
+	s := &stringer{3}
+	b := new(bytes.Buffer)
+	tmpl := Must(New("x").Parse("{{.}}"))
+	if err := tmpl.Execute(b, s); err != nil {
+		t.Fatal(err)
+	}
+	var expect = "string=3"
+	if b.String() != expect {
+		t.Errorf("expected %q got %q", expect, b.String())
+	}
+	e := &errorer{7}
+	b.Reset()
+	if err := tmpl.Execute(b, e); err != nil {
+		t.Fatal(err)
+	}
+	expect = "error=7"
+	if b.String() != expect {
+		t.Errorf("expected %q got %q", expect, b.String())
+	}
+}
diff --git a/libgo/go/html/template/doc.go b/libgo/go/html/template/doc.go
index 6fe507abea4..7f60f3b9680 100644
--- a/libgo/go/html/template/doc.go
+++ b/libgo/go/html/template/doc.go
@@ -17,11 +17,11 @@ Introduction
 This package wraps package text/template so you can share its template API
 to parse and execute HTML templates safely.
 
-  set, err := new(template.Set).Parse(...)
+  tmpl, err := template.New("name").Parse(...)
   // Error checking elided
-  err = set.Execute(out, "Foo", data)
+  err = tmpl.Execute(out, "Foo", data)
 
-If successful, set will now be injection-safe. Otherwise, err is an error
+If successful, tmpl will now be injection-safe. Otherwise, err is an error
 defined in the docs for ErrorCode.
 
 HTML templates treat data values as plain text which should be encoded so they
@@ -172,18 +172,18 @@ This package assumes that template authors are trusted, that Execute's data
 parameter is not, and seeks to preserve the properties below in the face
 of untrusted data:
 
-Structure Preservation Property
+Structure Preservation Property:
 "... when a template author writes an HTML tag in a safe templating language,
 the browser will interpret the corresponding portion of the output as a tag
 regardless of the values of untrusted data, and similarly for other structures
 such as attribute boundaries and JS and CSS string boundaries."
 
-Code Effect Property
+Code Effect Property:
 "... only code specified by the template author should run as a result of
 injecting the template output into a page and all code specified by the
 template author should run as a result of the same."
 
-Least Surprise Property
+Least Surprise Property:
 "A developer (or code reviewer) familiar with HTML, CSS, and JavaScript, who
 knows that contextual autoescaping happens should be able to look at a {{.}}
 and correctly infer what sanitization happens."
diff --git a/libgo/go/html/template/escape.go b/libgo/go/html/template/escape.go
index c6f723ae4a4..02fa3eaad6b 100644
--- a/libgo/go/html/template/escape.go
+++ b/libgo/go/html/template/escape.go
@@ -46,30 +46,30 @@ func escapeTemplates(tmpl *Template, names ...string) error {
 
 // funcMap maps command names to functions that render their inputs safe.
 var funcMap = template.FuncMap{
-	"exp_template_html_attrescaper":     attrEscaper,
-	"exp_template_html_commentescaper":  commentEscaper,
-	"exp_template_html_cssescaper":      cssEscaper,
-	"exp_template_html_cssvaluefilter":  cssValueFilter,
-	"exp_template_html_htmlnamefilter":  htmlNameFilter,
-	"exp_template_html_htmlescaper":     htmlEscaper,
-	"exp_template_html_jsregexpescaper": jsRegexpEscaper,
-	"exp_template_html_jsstrescaper":    jsStrEscaper,
-	"exp_template_html_jsvalescaper":    jsValEscaper,
-	"exp_template_html_nospaceescaper":  htmlNospaceEscaper,
-	"exp_template_html_rcdataescaper":   rcdataEscaper,
-	"exp_template_html_urlescaper":      urlEscaper,
-	"exp_template_html_urlfilter":       urlFilter,
-	"exp_template_html_urlnormalizer":   urlNormalizer,
+	"html_template_attrescaper":     attrEscaper,
+	"html_template_commentescaper":  commentEscaper,
+	"html_template_cssescaper":      cssEscaper,
+	"html_template_cssvaluefilter":  cssValueFilter,
+	"html_template_htmlnamefilter":  htmlNameFilter,
+	"html_template_htmlescaper":     htmlEscaper,
+	"html_template_jsregexpescaper": jsRegexpEscaper,
+	"html_template_jsstrescaper":    jsStrEscaper,
+	"html_template_jsvalescaper":    jsValEscaper,
+	"html_template_nospaceescaper":  htmlNospaceEscaper,
+	"html_template_rcdataescaper":   rcdataEscaper,
+	"html_template_urlescaper":      urlEscaper,
+	"html_template_urlfilter":       urlFilter,
+	"html_template_urlnormalizer":   urlNormalizer,
 }
 
 // equivEscapers matches contextual escapers to equivalent template builtins.
 var equivEscapers = map[string]string{
-	"exp_template_html_attrescaper":    "html",
-	"exp_template_html_htmlescaper":    "html",
-	"exp_template_html_nospaceescaper": "html",
-	"exp_template_html_rcdataescaper":  "html",
-	"exp_template_html_urlescaper":     "urlquery",
-	"exp_template_html_urlnormalizer":  "urlquery",
+	"html_template_attrescaper":    "html",
+	"html_template_htmlescaper":    "html",
+	"html_template_nospaceescaper": "html",
+	"html_template_rcdataescaper":  "html",
+	"html_template_urlescaper":     "urlquery",
+	"html_template_urlnormalizer":  "urlquery",
 }
 
 // escaper collects type inferences about templates and changes needed to make
@@ -147,17 +147,17 @@ func (e *escaper) escapeAction(c context, n *parse.ActionNode) context {
 	case stateURL, stateCSSDqStr, stateCSSSqStr, stateCSSDqURL, stateCSSSqURL, stateCSSURL:
 		switch c.urlPart {
 		case urlPartNone:
-			s = append(s, "exp_template_html_urlfilter")
+			s = append(s, "html_template_urlfilter")
 			fallthrough
 		case urlPartPreQuery:
 			switch c.state {
 			case stateCSSDqStr, stateCSSSqStr:
-				s = append(s, "exp_template_html_cssescaper")
+				s = append(s, "html_template_cssescaper")
 			default:
-				s = append(s, "exp_template_html_urlnormalizer")
+				s = append(s, "html_template_urlnormalizer")
 			}
 		case urlPartQueryOrFrag:
-			s = append(s, "exp_template_html_urlescaper")
+			s = append(s, "html_template_urlescaper")
 		case urlPartUnknown:
 			return context{
 				state: stateError,
@@ -167,27 +167,27 @@ func (e *escaper) escapeAction(c context, n *parse.ActionNode) context {
 			panic(c.urlPart.String())
 		}
 	case stateJS:
-		s = append(s, "exp_template_html_jsvalescaper")
+		s = append(s, "html_template_jsvalescaper")
 		// A slash after a value starts a div operator.
 		c.jsCtx = jsCtxDivOp
 	case stateJSDqStr, stateJSSqStr:
-		s = append(s, "exp_template_html_jsstrescaper")
+		s = append(s, "html_template_jsstrescaper")
 	case stateJSRegexp:
-		s = append(s, "exp_template_html_jsregexpescaper")
+		s = append(s, "html_template_jsregexpescaper")
 	case stateCSS:
-		s = append(s, "exp_template_html_cssvaluefilter")
+		s = append(s, "html_template_cssvaluefilter")
 	case stateText:
-		s = append(s, "exp_template_html_htmlescaper")
+		s = append(s, "html_template_htmlescaper")
 	case stateRCDATA:
-		s = append(s, "exp_template_html_rcdataescaper")
+		s = append(s, "html_template_rcdataescaper")
 	case stateAttr:
 		// Handled below in delim check.
 	case stateAttrName, stateTag:
 		c.state = stateAttrName
-		s = append(s, "exp_template_html_htmlnamefilter")
+		s = append(s, "html_template_htmlnamefilter")
 	default:
 		if isComment(c.state) {
-			s = append(s, "exp_template_html_commentescaper")
+			s = append(s, "html_template_commentescaper")
 		} else {
 			panic("unexpected state " + c.state.String())
 		}
@@ -196,9 +196,9 @@ func (e *escaper) escapeAction(c context, n *parse.ActionNode) context {
 	case delimNone:
 		// No extra-escaping needed for raw text content.
 	case delimSpaceOrTagEnd:
-		s = append(s, "exp_template_html_nospaceescaper")
+		s = append(s, "html_template_nospaceescaper")
 	default:
-		s = append(s, "exp_template_html_attrescaper")
+		s = append(s, "html_template_attrescaper")
 	}
 	e.editActionNode(n, s)
 	return c
@@ -260,22 +260,22 @@ func ensurePipelineContains(p *parse.PipeNode, s []string) {
 // redundantFuncs[a][b] implies that funcMap[b](funcMap[a](x)) == funcMap[a](x)
 // for all x.
 var redundantFuncs = map[string]map[string]bool{
-	"exp_template_html_commentescaper": {
-		"exp_template_html_attrescaper":    true,
-		"exp_template_html_nospaceescaper": true,
-		"exp_template_html_htmlescaper":    true,
+	"html_template_commentescaper": {
+		"html_template_attrescaper":    true,
+		"html_template_nospaceescaper": true,
+		"html_template_htmlescaper":    true,
 	},
-	"exp_template_html_cssescaper": {
-		"exp_template_html_attrescaper": true,
+	"html_template_cssescaper": {
+		"html_template_attrescaper": true,
 	},
-	"exp_template_html_jsregexpescaper": {
-		"exp_template_html_attrescaper": true,
+	"html_template_jsregexpescaper": {
+		"html_template_attrescaper": true,
 	},
-	"exp_template_html_jsstrescaper": {
-		"exp_template_html_attrescaper": true,
+	"html_template_jsstrescaper": {
+		"html_template_attrescaper": true,
 	},
-	"exp_template_html_urlescaper": {
-		"exp_template_html_urlnormalizer": true,
+	"html_template_urlescaper": {
+		"html_template_urlnormalizer": true,
 	},
 }
 
@@ -505,7 +505,7 @@ func (e *escaper) escapeTree(c context, name string, line int) (context, string)
 		dt := e.template(dname)
 		if dt == nil {
 			dt = template.New(dname)
-			dt.Tree = &parse.Tree{Name: dname, Root: cloneList(t.Root)}
+			dt.Tree = &parse.Tree{Name: dname, Root: t.Root.CopyList()}
 			e.derived[dname] = dt
 		}
 		t = dt
diff --git a/libgo/go/html/template/template.go b/libgo/go/html/template/template.go
index 9ffe41413a8..b0bae7a54fb 100644
--- a/libgo/go/html/template/template.go
+++ b/libgo/go/html/template/template.go
@@ -50,7 +50,7 @@ func (t *Template) Execute(wr io.Writer, data interface{}) (err error) {
 // ExecuteTemplate applies the template associated with t that has the given
 // name to the specified data object and writes the output to wr.
 func (t *Template) ExecuteTemplate(wr io.Writer, name string, data interface{}) error {
-	tmpl, err := t.lookupAndEscapeTemplate(wr, name)
+	tmpl, err := t.lookupAndEscapeTemplate(name)
 	if err != nil {
 		return err
 	}
@@ -60,7 +60,7 @@ func (t *Template) ExecuteTemplate(wr io.Writer, name string, data interface{})
 // lookupAndEscapeTemplate guarantees that the template with the given name
 // is escaped, or returns an error if it cannot be. It returns the named
 // template.
-func (t *Template) lookupAndEscapeTemplate(wr io.Writer, name string) (tmpl *Template, err error) {
+func (t *Template) lookupAndEscapeTemplate(name string) (tmpl *Template, err error) {
 	t.nameSpace.mu.Lock()
 	defer t.nameSpace.mu.Unlock()
 	tmpl = t.set[name]
@@ -106,14 +106,71 @@ func (t *Template) Parse(src string) (*Template, error) {
 	return t, nil
 }
 
-// AddParseTree is unimplemented.
-func (t *Template) AddParseTree(name string, tree *parse.Tree) error {
-	return fmt.Errorf("html/template: AddParseTree unimplemented")
+// AddParseTree creates a new template with the name and parse tree
+// and associates it with t.
+//
+// It returns an error if t has already been executed.
+func (t *Template) AddParseTree(name string, tree *parse.Tree) (*Template, error) {
+	t.nameSpace.mu.Lock()
+	defer t.nameSpace.mu.Unlock()
+	if t.escaped {
+		return nil, fmt.Errorf("html/template: cannot AddParseTree to %q after it has executed", t.Name())
+	}
+	text, err := t.text.AddParseTree(name, tree)
+	if err != nil {
+		return nil, err
+	}
+	ret := &Template{
+		false,
+		text,
+		t.nameSpace,
+	}
+	t.set[name] = ret
+	return ret, nil
 }
 
-// Clone is unimplemented.
-func (t *Template) Clone(name string) error {
-	return fmt.Errorf("html/template: Clone unimplemented")
+// Clone returns a duplicate of the template, including all associated
+// templates. The actual representation is not copied, but the name space of
+// associated templates is, so further calls to Parse in the copy will add
+// templates to the copy but not to the original. Clone can be used to prepare
+// common templates and use them with variant definitions for other templates
+// by adding the variants after the clone is made.
+//
+// It returns an error if t has already been executed.
+func (t *Template) Clone() (*Template, error) {
+	t.nameSpace.mu.Lock()
+	defer t.nameSpace.mu.Unlock()
+	if t.escaped {
+		return nil, fmt.Errorf("html/template: cannot Clone %q after it has executed", t.Name())
+	}
+	textClone, err := t.text.Clone()
+	if err != nil {
+		return nil, err
+	}
+	ret := &Template{
+		false,
+		textClone,
+		&nameSpace{
+			set: make(map[string]*Template),
+		},
+	}
+	for _, x := range textClone.Templates() {
+		name := x.Name()
+		src := t.set[name]
+		if src == nil || src.escaped {
+			return nil, fmt.Errorf("html/template: cannot Clone %q after it has executed", t.Name())
+		}
+		x.Tree = &parse.Tree{
+			Name: x.Tree.Name,
+			Root: x.Tree.Root.CopyList(),
+		}
+		ret.set[name] = &Template{
+			false,
+			x,
+			ret.nameSpace,
+		}
+	}
+	return ret, nil
 }
 
 // New allocates a new HTML template with the given name.
diff --git a/libgo/go/image/decode_example_test.go b/libgo/go/image/decode_example_test.go
new file mode 100644
index 00000000000..aa5a841c0a5
--- /dev/null
+++ b/libgo/go/image/decode_example_test.go
@@ -0,0 +1,79 @@
+// Copyright 2012 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.
+
+// This example demonstrates decoding a JPEG image and examining its pixels.
+package image_test
+
+import (
+	"fmt"
+	"image"
+	"log"
+	"os"
+
+	// Package image/jpeg is not used explicitly in the code below,
+	// but is imported for its initialization side-effect, which allows
+	// image.Decode to understand JPEG formatted images. Uncomment these
+	// two lines to also understand GIF and PNG images:
+	// _ "image/gif"
+	// _ "image/png"
+	_ "image/jpeg"
+)
+
+func Example() {
+	// Open the file.
+	file, err := os.Open("testdata/video-001.jpeg")
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer file.Close()
+
+	// Decode the image.
+	m, _, err := image.Decode(file)
+	if err != nil {
+		log.Fatal(err)
+	}
+	bounds := m.Bounds()
+
+	// Calculate a 16-bin histogram for m's red, green, blue and alpha components.
+	//
+	// An image's bounds do not necessarily start at (0, 0), so the two loops start
+	// at bounds.Min.Y and bounds.Min.X. Looping over Y first and X second is more
+	// likely to result in better memory access patterns than X first and Y second.
+	var histogram [16][4]int
+	for y := bounds.Min.Y; y < bounds.Max.Y; y++ {
+		for x := bounds.Min.X; x < bounds.Max.X; x++ {
+			r, g, b, a := m.At(x, y).RGBA()
+			// A color's RGBA method returns values in the range [0, 65535].
+			// Shifting by 12 reduces this to the range [0, 15].
+			histogram[r>>12][0]++
+			histogram[g>>12][1]++
+			histogram[b>>12][2]++
+			histogram[a>>12][3]++
+		}
+	}
+
+	// Print the results.
+	fmt.Printf("%-14s %6s %6s %6s %6s\n", "bin", "red", "green", "blue", "alpha")
+	for i, x := range histogram {
+		fmt.Printf("0x%04x-0x%04x: %6d %6d %6d %6d\n", i<<12, (i+1)<<12-1, x[0], x[1], x[2], x[3])
+	}
+	// Output:
+	// bin               red  green   blue  alpha
+	// 0x0000-0x0fff:    471    819   7596      0
+	// 0x1000-0x1fff:    576   2892    726      0
+	// 0x2000-0x2fff:   1038   2330    943      0
+	// 0x3000-0x3fff:    883   2321   1014      0
+	// 0x4000-0x4fff:    501   1295    525      0
+	// 0x5000-0x5fff:    302    962    242      0
+	// 0x6000-0x6fff:    219    358    150      0
+	// 0x7000-0x7fff:    352    281    192      0
+	// 0x8000-0x8fff:   3688    216    246      0
+	// 0x9000-0x9fff:   2277    237    283      0
+	// 0xa000-0xafff:    971    254    357      0
+	// 0xb000-0xbfff:    317    306    429      0
+	// 0xc000-0xcfff:    203    402    401      0
+	// 0xd000-0xdfff:    256    394    241      0
+	// 0xe000-0xefff:    378    343    173      0
+	// 0xf000-0xffff:   3018   2040   1932  15450
+}
diff --git a/libgo/go/image/ycbcr_test.go b/libgo/go/image/ycbcr_test.go
index eb8b1950bfe..b2373f79ba3 100644
--- a/libgo/go/image/ycbcr_test.go
+++ b/libgo/go/image/ycbcr_test.go
@@ -50,6 +50,9 @@ func TestYCbCr(t *testing.T) {
 				testYCbCr(t, r, subsampleRatio, delta)
 			}
 		}
+		if testing.Short() {
+			break
+		}
 	}
 }
 
diff --git a/libgo/go/io/ioutil/tempfile.go b/libgo/go/io/ioutil/tempfile.go
index 645eed6abb8..42d2e675869 100644
--- a/libgo/go/io/ioutil/tempfile.go
+++ b/libgo/go/io/ioutil/tempfile.go
@@ -49,7 +49,7 @@ func TempFile(dir, prefix string) (f *os.File, err error) {
 	for i := 0; i < 10000; i++ {
 		name := filepath.Join(dir, prefix+nextSuffix())
 		f, err = os.OpenFile(name, os.O_RDWR|os.O_CREATE|os.O_EXCL, 0600)
-		if pe, ok := err.(*os.PathError); ok && pe.Err == os.EEXIST {
+		if os.IsExist(err) {
 			if nconflict++; nconflict > 10 {
 				rand = reseed()
 			}
@@ -76,7 +76,7 @@ func TempDir(dir, prefix string) (name string, err error) {
 	for i := 0; i < 10000; i++ {
 		try := filepath.Join(dir, prefix+nextSuffix())
 		err = os.Mkdir(try, 0700)
-		if pe, ok := err.(*os.PathError); ok && pe.Err == os.EEXIST {
+		if os.IsExist(err) {
 			if nconflict++; nconflict > 10 {
 				rand = reseed()
 			}
diff --git a/libgo/go/log/syslog/syslog.go b/libgo/go/log/syslog/syslog.go
index 3eb5353e9a9..f53310cb0a1 100644
--- a/libgo/go/log/syslog/syslog.go
+++ b/libgo/go/log/syslog/syslog.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build !windows,!plan9
+
 // Package syslog provides a simple interface to the system log service. It
 // can send messages to the syslog daemon using UNIX domain sockets, UDP, or
 // TCP connections.
diff --git a/libgo/go/log/syslog/syslog_test.go b/libgo/go/log/syslog/syslog_test.go
index 7f509b3666e..0fd6239059a 100644
--- a/libgo/go/log/syslog/syslog_test.go
+++ b/libgo/go/log/syslog/syslog_test.go
@@ -1,6 +1,9 @@
 // Copyright 2009 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.
+
+// +build !windows,!plan9
+
 package syslog
 
 import (
diff --git a/libgo/go/log/syslog/syslog_unix.go b/libgo/go/log/syslog/syslog_unix.go
index b1c929ad2fe..46a164dd577 100644
--- a/libgo/go/log/syslog/syslog_unix.go
+++ b/libgo/go/log/syslog/syslog_unix.go
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// +build !windows,!plan9
+
 package syslog
 
 import (
diff --git a/libgo/go/math/big/nat_test.go b/libgo/go/math/big/nat_test.go
index 25e39273c0c..7f3f76dc36f 100644
--- a/libgo/go/math/big/nat_test.go
+++ b/libgo/go/math/big/nat_test.go
@@ -512,6 +512,9 @@ func TestStringPowers(t *testing.T) {
 				t.Errorf("failed at %d ** %d in base %d: %s != %s", b, p, b, xs, xs2)
 			}
 		}
+		if b >= 3 && testing.Short() {
+			break
+		}
 	}
 }
 
diff --git a/libgo/go/math/rand/rand.go b/libgo/go/math/rand/rand.go
index 89552192030..94f84a85fbe 100644
--- a/libgo/go/math/rand/rand.go
+++ b/libgo/go/math/rand/rand.go
@@ -49,9 +49,10 @@ func (r *Rand) Int() int {
 }
 
 // Int63n returns, as an int64, a non-negative pseudo-random number in [0,n).
+// It panics if n <= 0.
 func (r *Rand) Int63n(n int64) int64 {
 	if n <= 0 {
-		return 0
+		panic("invalid argument to Int63n")
 	}
 	max := int64((1 << 63) - 1 - (1<<63)%uint64(n))
 	v := r.Int63()
@@ -62,9 +63,10 @@ func (r *Rand) Int63n(n int64) int64 {
 }
 
 // Int31n returns, as an int32, a non-negative pseudo-random number in [0,n).
+// It panics if n <= 0.
 func (r *Rand) Int31n(n int32) int32 {
 	if n <= 0 {
-		return 0
+		panic("invalid argument to Int31n")
 	}
 	max := int32((1 << 31) - 1 - (1<<31)%uint32(n))
 	v := r.Int31()
@@ -75,7 +77,11 @@ func (r *Rand) Int31n(n int32) int32 {
 }
 
 // Intn returns, as an int, a non-negative pseudo-random number in [0,n).
+// It panics if n <= 0.
 func (r *Rand) Intn(n int) int {
+	if n <= 0 {
+		panic("invalid argument to Intn")
+	}
 	if n <= 1<<31-1 {
 		return int(r.Int31n(int32(n)))
 	}
@@ -125,12 +131,15 @@ func Int31() int32 { return globalRand.Int31() }
 func Int() int { return globalRand.Int() }
 
 // Int63n returns, as an int64, a non-negative pseudo-random number in [0,n).
+// It panics if n <= 0.
 func Int63n(n int64) int64 { return globalRand.Int63n(n) }
 
 // Int31n returns, as an int32, a non-negative pseudo-random number in [0,n).
+// It panics if n <= 0.
 func Int31n(n int32) int32 { return globalRand.Int31n(n) }
 
 // Intn returns, as an int, a non-negative pseudo-random number in [0,n).
+// It panics if n <= 0.
 func Intn(n int) int { return globalRand.Intn(n) }
 
 // Float64 returns, as a float64, a pseudo-random number in [0.0,1.0).
diff --git a/libgo/go/math/rand/rand_test.go b/libgo/go/math/rand/rand_test.go
index 0ba8f98c496..bbd44e3f8b1 100644
--- a/libgo/go/math/rand/rand_test.go
+++ b/libgo/go/math/rand/rand_test.go
@@ -141,6 +141,9 @@ func TestNonStandardNormalValues(t *testing.T) {
 		for m := 0.5; m < mmax; m *= 2 {
 			for _, seed := range testSeeds {
 				testNormalDistribution(t, numTestSamples, m, sd, seed)
+				if testing.Short() {
+					break
+				}
 			}
 		}
 	}
@@ -191,6 +194,9 @@ func TestNonStandardExponentialValues(t *testing.T) {
 	for rate := 0.05; rate < 10; rate *= 2 {
 		for _, seed := range testSeeds {
 			testExponentialDistribution(t, numTestSamples, rate, seed)
+			if testing.Short() {
+				break
+			}
 		}
 	}
 }
diff --git a/libgo/go/net/dialgoogle_test.go b/libgo/go/net/dialgoogle_test.go
index 81750a3d739..14356da4ce3 100644
--- a/libgo/go/net/dialgoogle_test.go
+++ b/libgo/go/net/dialgoogle_test.go
@@ -14,7 +14,7 @@ import (
 )
 
 // If an IPv6 tunnel is running, we can try dialing a real IPv6 address.
-var ipv6 = flag.Bool("ipv6", false, "assume ipv6 tunnel is present")
+var testIPv6 = flag.Bool("ipv6", false, "assume ipv6 tunnel is present")
 
 // fd is already connected to the destination, port 80.
 // Run an HTTP request to fetch the appropriate page.
@@ -130,7 +130,7 @@ func TestDialGoogleIPv6(t *testing.T) {
 		return
 	}
 	// Only run tcp6 if the kernel will take it.
-	if !*ipv6 || !supportsIPv6 {
+	if !*testIPv6 || !supportsIPv6 {
 		return
 	}
 
diff --git a/libgo/go/net/fd.go b/libgo/go/net/fd.go
index bf0a387775d..ae1bf2614a2 100644
--- a/libgo/go/net/fd.go
+++ b/libgo/go/net/fd.go
@@ -252,7 +252,9 @@ func (s *pollServer) Run() {
 		} else {
 			netfd := s.LookupFD(fd, mode)
 			if netfd == nil {
-				print("pollServer: unexpected wakeup for fd=", fd, " mode=", string(mode), "\n")
+				// This can happen because the WaitFD runs without
+				// holding s's lock, so there might be a pending wakeup
+				// for an fd that has been evicted.  No harm done.
 				continue
 			}
 			s.WakeFD(netfd, mode, nil)
@@ -506,7 +508,7 @@ func (fd *netFD) Write(p []byte) (int, error) {
 	}
 	defer fd.decref()
 	if fd.sysfile == nil {
-		return 0, os.EINVAL
+		return 0, syscall.EINVAL
 	}
 
 	var err error
diff --git a/libgo/go/net/fd_windows.go b/libgo/go/net/fd_windows.go
index efd846e5d8c..45f5c2d882f 100644
--- a/libgo/go/net/fd_windows.go
+++ b/libgo/go/net/fd_windows.go
@@ -335,7 +335,7 @@ func (fd *netFD) Close() error {
 
 func (fd *netFD) shutdown(how int) error {
 	if fd == nil || fd.sysfd == syscall.InvalidHandle {
-		return os.EINVAL
+		return syscall.EINVAL
 	}
 	err := syscall.Shutdown(fd.sysfd, how)
 	if err != nil {
@@ -369,7 +369,7 @@ func (o *readOp) Name() string {
 
 func (fd *netFD) Read(buf []byte) (int, error) {
 	if fd == nil {
-		return 0, os.EINVAL
+		return 0, syscall.EINVAL
 	}
 	fd.rio.Lock()
 	defer fd.rio.Unlock()
@@ -378,7 +378,7 @@ func (fd *netFD) Read(buf []byte) (int, error) {
 	}
 	defer fd.decref()
 	if fd.sysfd == syscall.InvalidHandle {
-		return 0, os.EINVAL
+		return 0, syscall.EINVAL
 	}
 	var o readOp
 	o.Init(fd, buf, 'r')
@@ -408,7 +408,7 @@ func (o *readFromOp) Name() string {
 
 func (fd *netFD) ReadFrom(buf []byte) (n int, sa syscall.Sockaddr, err error) {
 	if fd == nil {
-		return 0, nil, os.EINVAL
+		return 0, nil, syscall.EINVAL
 	}
 	if len(buf) == 0 {
 		return 0, nil, nil
@@ -447,7 +447,7 @@ func (o *writeOp) Name() string {
 
 func (fd *netFD) Write(buf []byte) (int, error) {
 	if fd == nil {
-		return 0, os.EINVAL
+		return 0, syscall.EINVAL
 	}
 	fd.wio.Lock()
 	defer fd.wio.Unlock()
@@ -478,7 +478,7 @@ func (o *writeToOp) Name() string {
 
 func (fd *netFD) WriteTo(buf []byte, sa syscall.Sockaddr) (int, error) {
 	if fd == nil {
-		return 0, os.EINVAL
+		return 0, syscall.EINVAL
 	}
 	if len(buf) == 0 {
 		return 0, nil
@@ -490,7 +490,7 @@ func (fd *netFD) WriteTo(buf []byte, sa syscall.Sockaddr) (int, error) {
 	}
 	defer fd.decref()
 	if fd.sysfd == syscall.InvalidHandle {
-		return 0, os.EINVAL
+		return 0, syscall.EINVAL
 	}
 	var o writeToOp
 	o.Init(fd, buf, 'w')
@@ -578,10 +578,12 @@ func (fd *netFD) dup() (*os.File, error) {
 	return nil, os.NewSyscallError("dup", syscall.EWINDOWS)
 }
 
+var errNoSupport = errors.New("address family not supported")
+
 func (fd *netFD) ReadMsg(p []byte, oob []byte) (n, oobn, flags int, sa syscall.Sockaddr, err error) {
-	return 0, 0, 0, nil, os.EAFNOSUPPORT
+	return 0, 0, 0, nil, errNoSupport
 }
 
 func (fd *netFD) WriteMsg(p []byte, oob []byte, sa syscall.Sockaddr) (n int, oobn int, err error) {
-	return 0, 0, os.EAFNOSUPPORT
+	return 0, 0, errNoSupport
 }
diff --git a/libgo/go/net/file.go b/libgo/go/net/file.go
index f9546dc930d..c95d16d64e7 100644
--- a/libgo/go/net/file.go
+++ b/libgo/go/net/file.go
@@ -28,7 +28,7 @@ func newFileFD(f *os.File) (*netFD, error) {
 	switch sa.(type) {
 	default:
 		closesocket(fd)
-		return nil, os.EINVAL
+		return nil, syscall.EINVAL
 	case *syscall.SockaddrInet4:
 		family = syscall.AF_INET
 		if proto == syscall.SOCK_DGRAM {
@@ -84,7 +84,7 @@ func FileConn(f *os.File) (c Conn, err error) {
 		return newIPConn(fd), nil
 	}
 	fd.Close()
-	return nil, os.EINVAL
+	return nil, syscall.EINVAL
 }
 
 // FileListener returns a copy of the network listener corresponding
@@ -103,7 +103,7 @@ func FileListener(f *os.File) (l Listener, err error) {
 		return &UnixListener{fd, laddr.Name}, nil
 	}
 	fd.Close()
-	return nil, os.EINVAL
+	return nil, syscall.EINVAL
 }
 
 // FilePacketConn returns a copy of the packet network connection
@@ -122,5 +122,5 @@ func FilePacketConn(f *os.File) (c PacketConn, err error) {
 		return newUnixConn(fd), nil
 	}
 	fd.Close()
-	return nil, os.EINVAL
+	return nil, syscall.EINVAL
 }
diff --git a/libgo/go/net/file_plan9.go b/libgo/go/net/file_plan9.go
index 06d7cc89846..04f7ee0401b 100644
--- a/libgo/go/net/file_plan9.go
+++ b/libgo/go/net/file_plan9.go
@@ -6,6 +6,7 @@ package net
 
 import (
 	"os"
+	"syscall"
 )
 
 // FileConn returns a copy of the network connection corresponding to
@@ -13,7 +14,7 @@ import (
 // finished.  Closing c does not affect f, and closing f does not
 // affect c.
 func FileConn(f *os.File) (c Conn, err error) {
-	return nil, os.EPLAN9
+	return nil, syscall.EPLAN9
 }
 
 // FileListener returns a copy of the network listener corresponding
@@ -21,7 +22,7 @@ func FileConn(f *os.File) (c Conn, err error) {
 // when finished.  Closing c does not affect l, and closing l does not
 // affect c.
 func FileListener(f *os.File) (l Listener, err error) {
-	return nil, os.EPLAN9
+	return nil, syscall.EPLAN9
 }
 
 // FilePacketConn returns a copy of the packet network connection
@@ -29,5 +30,5 @@ func FileListener(f *os.File) (l Listener, err error) {
 // responsibility to close f when finished.  Closing c does not affect
 // f, and closing f does not affect c.
 func FilePacketConn(f *os.File) (c PacketConn, err error) {
-	return nil, os.EPLAN9
+	return nil, syscall.EPLAN9
 }
diff --git a/libgo/go/net/hosts_test.go b/libgo/go/net/hosts_test.go
index 1bd00541c6d..064e7e43282 100644
--- a/libgo/go/net/hosts_test.go
+++ b/libgo/go/net/hosts_test.go
@@ -34,7 +34,7 @@ var hosttests = []hostTest{
 
 func TestLookupStaticHost(t *testing.T) {
 	p := hostsPath
-	hostsPath = "hosts_testdata"
+	hostsPath = "testdata/hosts"
 	for i := 0; i < len(hosttests); i++ {
 		tt := hosttests[i]
 		ips := lookupStaticHost(tt.host)
diff --git a/libgo/go/net/http/cookie_test.go b/libgo/go/net/http/cookie_test.go
index 712350dfcef..1e9186a0581 100644
--- a/libgo/go/net/http/cookie_test.go
+++ b/libgo/go/net/http/cookie_test.go
@@ -128,6 +128,34 @@ var readSetCookiesTests = []struct {
 			Raw:        "NID=99=YsDT5i3E-CXax-; expires=Wed, 23-Nov-2011 01:05:03 GMT; path=/; domain=.google.ch; HttpOnly",
 		}},
 	},
+	{
+		Header{"Set-Cookie": {".ASPXAUTH=7E3AA; expires=Wed, 07-Mar-2012 14:25:06 GMT; path=/; HttpOnly"}},
+		[]*Cookie{{
+			Name:       ".ASPXAUTH",
+			Value:      "7E3AA",
+			Path:       "/",
+			Expires:    time.Date(2012, 3, 7, 14, 25, 6, 0, time.UTC),
+			RawExpires: "Wed, 07-Mar-2012 14:25:06 GMT",
+			HttpOnly:   true,
+			Raw:        ".ASPXAUTH=7E3AA; expires=Wed, 07-Mar-2012 14:25:06 GMT; path=/; HttpOnly",
+		}},
+	},
+	{
+		Header{"Set-Cookie": {"ASP.NET_SessionId=foo; path=/; HttpOnly"}},
+		[]*Cookie{{
+			Name:     "ASP.NET_SessionId",
+			Value:    "foo",
+			Path:     "/",
+			HttpOnly: true,
+			Raw:      "ASP.NET_SessionId=foo; path=/; HttpOnly",
+		}},
+	},
+
+	// TODO(bradfitz): users have reported seeing this in the
+	// wild, but do browsers handle it? RFC 6265 just says "don't
+	// do that" (section 3) and then never mentions header folding
+	// again.
+	// Header{"Set-Cookie": {"ASP.NET_SessionId=foo; path=/; HttpOnly, .ASPXAUTH=7E3AA; expires=Wed, 07-Mar-2012 14:25:06 GMT; path=/; HttpOnly"}},
 }
 
 func toJSON(v interface{}) string {
diff --git a/libgo/go/net/http/example_test.go b/libgo/go/net/http/example_test.go
new file mode 100644
index 00000000000..2584afc439e
--- /dev/null
+++ b/libgo/go/net/http/example_test.go
@@ -0,0 +1,51 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package http_test
+
+import (
+	"fmt"
+	"io/ioutil"
+	"log"
+	"net/http"
+)
+
+func ExampleHijacker() {
+	http.HandleFunc("/hijack", func(w http.ResponseWriter, r *http.Request) {
+		hj, ok := w.(http.Hijacker)
+		if !ok {
+			http.Error(w, "webserver doesn't support hijacking", http.StatusInternalServerError)
+			return
+		}
+		conn, bufrw, err := hj.Hijack()
+		if err != nil {
+			http.Error(w, err.Error(), http.StatusInternalServerError)
+			return
+		}
+		// Don't forget to close the connection:
+		defer conn.Close()
+		bufrw.WriteString("Now we're speaking raw TCP. Say hi: ")
+		bufrw.Flush()
+		s, err := bufrw.ReadString('\n')
+		if err != nil {
+			log.Printf("error reading string: %v", err)
+			return
+		}
+		fmt.Fprintf(bufrw, "You said: %q\nBye.\n", s)
+		bufrw.Flush()
+	})
+}
+
+func ExampleGet() {
+	res, err := http.Get("http://www.google.com/robots.txt")
+	if err != nil {
+		log.Fatal(err)
+	}
+	robots, err := ioutil.ReadAll(res.Body)
+	if err != nil {
+		log.Fatal(err)
+	}
+	res.Body.Close()
+	fmt.Printf("%s", robots)
+}
diff --git a/libgo/go/net/http/fs_test.go b/libgo/go/net/http/fs_test.go
index 143617e95fc..0409008b675 100644
--- a/libgo/go/net/http/fs_test.go
+++ b/libgo/go/net/http/fs_test.go
@@ -6,6 +6,7 @@ package http_test
 
 import (
 	"bytes"
+	"errors"
 	"fmt"
 	"io"
 	"io/ioutil"
@@ -131,7 +132,7 @@ func TestFileServerCleans(t *testing.T) {
 	ch := make(chan string, 1)
 	fs := FileServer(&testFileSystem{func(name string) (File, error) {
 		ch <- name
-		return nil, os.ENOENT
+		return nil, errors.New("file does not exist")
 	}})
 	tests := []struct {
 		reqPath, openArg string
@@ -398,11 +399,15 @@ func TestLinuxSendfile(t *testing.T) {
 		return
 	}
 
-	_, err = Get(fmt.Sprintf("http://%s/", ln.Addr()))
+	res, err := Get(fmt.Sprintf("http://%s/", ln.Addr()))
 	if err != nil {
-		t.Errorf("http client error: %v", err)
-		return
+		t.Fatalf("http client error: %v", err)
+	}
+	_, err = io.Copy(ioutil.Discard, res.Body)
+	if err != nil {
+		t.Fatalf("client body read error: %v", err)
 	}
+	res.Body.Close()
 
 	// Force child to exit cleanly.
 	Get(fmt.Sprintf("http://%s/quit", ln.Addr()))
diff --git a/libgo/go/net/http/httputil/persist.go b/libgo/go/net/http/httputil/persist.go
index c065ccfb499..32f4662cc0e 100644
--- a/libgo/go/net/http/httputil/persist.go
+++ b/libgo/go/net/http/httputil/persist.go
@@ -13,12 +13,12 @@ import (
 	"net"
 	"net/http"
 	"net/textproto"
-	"os"
 	"sync"
 )
 
 var (
 	ErrPersistEOF = &http.ProtocolError{ErrorString: "persistent connection closed"}
+	ErrClosed     = &http.ProtocolError{ErrorString: "connection closed by user"}
 	ErrPipeline   = &http.ProtocolError{ErrorString: "pipeline error"}
 )
 
@@ -191,7 +191,7 @@ func (sc *ServerConn) Write(req *http.Request, resp *http.Response) error {
 	}
 	if sc.c == nil { // connection closed by user in the meantime
 		defer sc.lk.Unlock()
-		return os.EBADF
+		return ErrClosed
 	}
 	c := sc.c
 	if sc.nread <= sc.nwritten {
diff --git a/libgo/go/net/http/pprof/pprof.go b/libgo/go/net/http/pprof/pprof.go
index 0fe41b7d31b..06fcde1447f 100644
--- a/libgo/go/net/http/pprof/pprof.go
+++ b/libgo/go/net/http/pprof/pprof.go
@@ -22,9 +22,9 @@
 //
 //	go tool pprof http://localhost:6060/debug/pprof/profile
 //
-// Or to look at the thread creation profile:
+// Or to view all available profiles:
 //
-//	go tool pprof http://localhost:6060/debug/pprof/thread
+//	go tool pprof http://localhost:6060/debug/pprof/
 //
 // For a study of the facility in action, visit
 //
@@ -36,7 +36,9 @@ import (
 	"bufio"
 	"bytes"
 	"fmt"
+	"html/template"
 	"io"
+	"log"
 	"net/http"
 	"os"
 	"runtime"
@@ -47,11 +49,10 @@ import (
 )
 
 func init() {
+	http.Handle("/debug/pprof/", http.HandlerFunc(Index))
 	http.Handle("/debug/pprof/cmdline", http.HandlerFunc(Cmdline))
 	http.Handle("/debug/pprof/profile", http.HandlerFunc(Profile))
-	http.Handle("/debug/pprof/heap", http.HandlerFunc(Heap))
 	http.Handle("/debug/pprof/symbol", http.HandlerFunc(Symbol))
-	http.Handle("/debug/pprof/thread", http.HandlerFunc(Thread))
 }
 
 // Cmdline responds with the running program's
@@ -62,20 +63,6 @@ func Cmdline(w http.ResponseWriter, r *http.Request) {
 	fmt.Fprintf(w, strings.Join(os.Args, "\x00"))
 }
 
-// Heap responds with the pprof-formatted heap profile.
-// The package initialization registers it as /debug/pprof/heap.
-func Heap(w http.ResponseWriter, r *http.Request) {
-	w.Header().Set("Content-Type", "text/plain; charset=utf-8")
-	pprof.WriteHeapProfile(w)
-}
-
-// Thread responds with the pprof-formatted thread creation profile.
-// The package initialization registers it as /debug/pprof/thread.
-func Thread(w http.ResponseWriter, r *http.Request) {
-	w.Header().Set("Content-Type", "text/plain; charset=utf-8")
-	pprof.WriteThreadProfile(w)
-}
-
 // Profile responds with the pprof-formatted cpu profile.
 // The package initialization registers it as /debug/pprof/profile.
 func Profile(w http.ResponseWriter, r *http.Request) {
@@ -147,3 +134,61 @@ func Symbol(w http.ResponseWriter, r *http.Request) {
 
 	w.Write(buf.Bytes())
 }
+
+// Handler returns an HTTP handler that serves the named profile.
+func Handler(name string) http.Handler {
+	return handler(name)
+}
+
+type handler string
+
+func (name handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	w.Header().Set("Content-Type", "text/plain; charset=utf-8")
+	debug, _ := strconv.Atoi(r.FormValue("debug"))
+	p := pprof.Lookup(string(name))
+	if p == nil {
+		w.WriteHeader(404)
+		fmt.Fprintf(w, "Unknown profile: %s\n", name)
+		return
+	}
+	p.WriteTo(w, debug)
+	return
+}
+
+// Index responds with the pprof-formatted profile named by the request.
+// For example, "/debug/pprof/heap" serves the "heap" profile.
+// Index responds to a request for "/debug/pprof/" with an HTML page
+// listing the available profiles.
+func Index(w http.ResponseWriter, r *http.Request) {
+	if strings.HasPrefix(r.URL.Path, "/debug/pprof/") {
+		name := r.URL.Path[len("/debug/pprof/"):]
+		if name != "" {
+			handler(name).ServeHTTP(w, r)
+			return
+		}
+	}
+
+	profiles := pprof.Profiles()
+	if err := indexTmpl.Execute(w, profiles); err != nil {
+		log.Print(err)
+	}
+}
+
+var indexTmpl = template.Must(template.New("index").Parse(`<html>
+<head>
+<title>/debug/pprof/</title>
+</head>
+/debug/pprof/<br>
+<br>
+<body>
+profiles:<br>
+<table>
+{{range .}}
+<tr><td align=right>{{.Count}}<td><a href="/debug/pprof/{{.Name}}?debug=1">{{.Name}}</a>
+{{end}}
+</table>
+<br>
+<a href="/debug/pprof/goroutine?debug=2">full goroutine stack dump</a><br>
+</body>
+</html>
+`))
diff --git a/libgo/go/net/http/request.go b/libgo/go/net/http/request.go
index 0bbec53be71..5277657805d 100644
--- a/libgo/go/net/http/request.go
+++ b/libgo/go/net/http/request.go
@@ -186,7 +186,7 @@ func (r *Request) Cookies() []*Cookie {
 	return readCookies(r.Header, "")
 }
 
-var ErrNoCookie = errors.New("http: named cookied not present")
+var ErrNoCookie = errors.New("http: named cookie not present")
 
 // Cookie returns the named cookie provided in the request or
 // ErrNoCookie if not found.
@@ -486,7 +486,7 @@ func ReadRequest(b *bufio.Reader) (req *Request, err error) {
 		rawurl = "http://" + rawurl
 	}
 
-	if req.URL, err = url.ParseRequest(rawurl); err != nil {
+	if req.URL, err = url.ParseRequestURI(rawurl); err != nil {
 		return nil, err
 	}
 
diff --git a/libgo/go/net/http/serve_test.go b/libgo/go/net/http/serve_test.go
index e2860c3edcf..b6a6b4c77d1 100644
--- a/libgo/go/net/http/serve_test.go
+++ b/libgo/go/net/http/serve_test.go
@@ -245,8 +245,7 @@ func TestServerTimeouts(t *testing.T) {
 		fmt.Fprintf(res, "req=%d", reqNum)
 	})
 
-	const second = 1000000000 /* nanos */
-	server := &Server{Handler: handler, ReadTimeout: 0.25 * second, WriteTimeout: 0.25 * second}
+	server := &Server{Handler: handler, ReadTimeout: 250 * time.Millisecond, WriteTimeout: 250 * time.Millisecond}
 	go server.Serve(l)
 
 	url := fmt.Sprintf("http://%s/", addr)
@@ -277,7 +276,7 @@ func TestServerTimeouts(t *testing.T) {
 	if n != 0 || err != io.EOF {
 		t.Errorf("Read = %v, %v, wanted %v, %v", n, err, 0, io.EOF)
 	}
-	if latency < 200*time.Millisecond /* fudge from 0.25 above */ {
+	if latency < 200*time.Millisecond /* fudge from 250 ms above */ {
 		t.Errorf("got EOF after %s, want >= %s", latency, 200*time.Millisecond)
 	}
 
diff --git a/libgo/go/net/http/server.go b/libgo/go/net/http/server.go
index e715c73cb6e..fa0df54a236 100644
--- a/libgo/go/net/http/server.go
+++ b/libgo/go/net/http/server.go
@@ -12,7 +12,6 @@ package http
 import (
 	"bufio"
 	"bytes"
-	"crypto/rand"
 	"crypto/tls"
 	"errors"
 	"fmt"
@@ -985,6 +984,7 @@ type Server struct {
 	ReadTimeout    time.Duration // maximum duration before timing out read of the request
 	WriteTimeout   time.Duration // maximum duration before timing out write of the response
 	MaxHeaderBytes int           // maximum size of request headers, DefaultMaxHeaderBytes if 0
+	TLSConfig      *tls.Config   // optional TLS config, used by ListenAndServeTLS
 }
 
 // ListenAndServe listens on the TCP network address srv.Addr and then
@@ -1121,9 +1121,12 @@ func (srv *Server) ListenAndServeTLS(certFile, keyFile string) error {
 	if addr == "" {
 		addr = ":https"
 	}
-	config := &tls.Config{
-		Rand:       rand.Reader,
-		NextProtos: []string{"http/1.1"},
+	config := &tls.Config{}
+	if srv.TLSConfig != nil {
+		*config = *srv.TLSConfig
+	}
+	if config.NextProtos == nil {
+		config.NextProtos = []string{"http/1.1"}
 	}
 
 	var err error
diff --git a/libgo/go/net/http/transport_test.go b/libgo/go/net/http/transport_test.go
index a36571a4446..1a629c1727c 100644
--- a/libgo/go/net/http/transport_test.go
+++ b/libgo/go/net/http/transport_test.go
@@ -648,7 +648,7 @@ func TestTransportPersistConnLeak(t *testing.T) {
 	tr := &Transport{}
 	c := &Client{Transport: tr}
 
-	n0 := runtime.Goroutines()
+	n0 := runtime.NumGoroutine()
 
 	const numReq = 25
 	didReqCh := make(chan bool)
@@ -669,7 +669,7 @@ func TestTransportPersistConnLeak(t *testing.T) {
 		<-gotReqCh
 	}
 
-	nhigh := runtime.Goroutines()
+	nhigh := runtime.NumGoroutine()
 
 	// Tell all handlers to unblock and reply.
 	for i := 0; i < numReq; i++ {
@@ -685,7 +685,7 @@ func TestTransportPersistConnLeak(t *testing.T) {
 	time.Sleep(100 * time.Millisecond)
 	runtime.GC()
 	runtime.GC() // even more.
-	nfinal := runtime.Goroutines()
+	nfinal := runtime.NumGoroutine()
 
 	growth := nfinal - n0
 
diff --git a/libgo/go/net/interface_linux.go b/libgo/go/net/interface_linux.go
index 21038c629b1..15c2f3781b1 100644
--- a/libgo/go/net/interface_linux.go
+++ b/libgo/go/net/interface_linux.go
@@ -166,13 +166,13 @@ func interfaceMulticastAddrTable(ifindex int) ([]Addr, error) {
 			return nil, err
 		}
 	}
-	ifmat4 := parseProcNetIGMP(ifi)
-	ifmat6 := parseProcNetIGMP6(ifi)
+	ifmat4 := parseProcNetIGMP("/proc/net/igmp", ifi)
+	ifmat6 := parseProcNetIGMP6("/proc/net/igmp6", ifi)
 	return append(ifmat4, ifmat6...), nil
 }
 
-func parseProcNetIGMP(ifi *Interface) []Addr {
-	fd, err := open("/proc/net/igmp")
+func parseProcNetIGMP(path string, ifi *Interface) []Addr {
+	fd, err := open(path)
 	if err != nil {
 		return nil
 	}
@@ -185,23 +185,26 @@ func parseProcNetIGMP(ifi *Interface) []Addr {
 	fd.readLine() // skip first line
 	b := make([]byte, IPv4len)
 	for l, ok := fd.readLine(); ok; l, ok = fd.readLine() {
-		f := getFields(l)
-		switch len(f) {
-		case 4:
+		f := splitAtBytes(l, " :\r\t\n")
+		if len(f) < 4 {
+			continue
+		}
+		switch {
+		case l[0] != ' ' && l[0] != '\t': // new interface line
+			name = f[1]
+		case len(f[0]) == 8:
 			if ifi == nil || name == ifi.Name {
 				fmt.Sscanf(f[0], "%08x", &b)
 				ifma := IPAddr{IP: IPv4(b[3], b[2], b[1], b[0])}
 				ifmat = append(ifmat, ifma.toAddr())
 			}
-		case 5:
-			name = f[1]
 		}
 	}
 	return ifmat
 }
 
-func parseProcNetIGMP6(ifi *Interface) []Addr {
-	fd, err := open("/proc/net/igmp6")
+func parseProcNetIGMP6(path string, ifi *Interface) []Addr {
+	fd, err := open(path)
 	if err != nil {
 		return nil
 	}
@@ -210,7 +213,10 @@ func parseProcNetIGMP6(ifi *Interface) []Addr {
 	var ifmat []Addr
 	b := make([]byte, IPv6len)
 	for l, ok := fd.readLine(); ok; l, ok = fd.readLine() {
-		f := getFields(l)
+		f := splitAtBytes(l, " \r\t\n")
+		if len(f) < 6 {
+			continue
+		}
 		if ifi == nil || f[1] == ifi.Name {
 			fmt.Sscanf(f[2], "%32x", &b)
 			ifma := IPAddr{IP: IP{b[0], b[1], b[2], b[3], b[4], b[5], b[6], b[7], b[8], b[9], b[10], b[11], b[12], b[13], b[14], b[15]}}
diff --git a/libgo/go/net/interface_test.go b/libgo/go/net/interface_test.go
index 4ce01dc9061..769414e0eef 100644
--- a/libgo/go/net/interface_test.go
+++ b/libgo/go/net/interface_test.go
@@ -31,17 +31,17 @@ func TestInterfaces(t *testing.T) {
 	for _, ifi := range ift {
 		ifxi, err := InterfaceByIndex(ifi.Index)
 		if err != nil {
-			t.Fatalf("InterfaceByIndex(%#q) failed: %v", ifi.Index, err)
+			t.Fatalf("InterfaceByIndex(%q) failed: %v", ifi.Index, err)
 		}
 		if !sameInterface(ifxi, &ifi) {
-			t.Fatalf("InterfaceByIndex(%#q) = %v, want %v", ifi.Index, *ifxi, ifi)
+			t.Fatalf("InterfaceByIndex(%q) = %v, want %v", ifi.Index, *ifxi, ifi)
 		}
 		ifxn, err := InterfaceByName(ifi.Name)
 		if err != nil {
-			t.Fatalf("InterfaceByName(%#q) failed: %v", ifi.Name, err)
+			t.Fatalf("InterfaceByName(%q) failed: %v", ifi.Name, err)
 		}
 		if !sameInterface(ifxn, &ifi) {
-			t.Fatalf("InterfaceByName(%#q) = %v, want %v", ifi.Name, *ifxn, ifi)
+			t.Fatalf("InterfaceByName(%q) = %v, want %v", ifi.Name, *ifxn, ifi)
 		}
 		t.Logf("%q: flags %q, ifindex %v, mtu %v\n", ifi.Name, ifi.Flags.String(), ifi.Index, ifi.MTU)
 		t.Logf("\thardware address %q", ifi.HardwareAddr.String())
diff --git a/libgo/go/net/ipraw_test.go b/libgo/go/net/ipraw_test.go
index f9401c1104e..6136202727c 100644
--- a/libgo/go/net/ipraw_test.go
+++ b/libgo/go/net/ipraw_test.go
@@ -7,6 +7,7 @@ package net
 import (
 	"bytes"
 	"os"
+	"syscall"
 	"testing"
 	"time"
 )
@@ -15,7 +16,7 @@ var icmpTests = []struct {
 	net   string
 	laddr string
 	raddr string
-	ipv6  bool
+	ipv6  bool // test with underlying AF_INET6 socket
 }{
 	{"ip4:icmp", "", "127.0.0.1", false},
 	{"ip6:icmp", "", "::1", true},
@@ -34,15 +35,15 @@ func TestICMP(t *testing.T) {
 		}
 		id := os.Getpid() & 0xffff
 		seqnum++
-		echo := newICMPEchoRequest(tt.ipv6, id, seqnum, 128, []byte("Go Go Gadget Ping!!!"))
-		exchangeICMPEcho(t, tt.net, tt.laddr, tt.raddr, tt.ipv6, echo)
+		echo := newICMPEchoRequest(tt.net, id, seqnum, 128, []byte("Go Go Gadget Ping!!!"))
+		exchangeICMPEcho(t, tt.net, tt.laddr, tt.raddr, echo)
 	}
 }
 
-func exchangeICMPEcho(t *testing.T, net, laddr, raddr string, ipv6 bool, echo []byte) {
+func exchangeICMPEcho(t *testing.T, net, laddr, raddr string, echo []byte) {
 	c, err := ListenPacket(net, laddr)
 	if err != nil {
-		t.Errorf("ListenPacket(%#q, %#q) failed: %v", net, laddr, err)
+		t.Errorf("ListenPacket(%q, %q) failed: %v", net, laddr, err)
 		return
 	}
 	c.SetDeadline(time.Now().Add(100 * time.Millisecond))
@@ -50,12 +51,12 @@ func exchangeICMPEcho(t *testing.T, net, laddr, raddr string, ipv6 bool, echo []
 
 	ra, err := ResolveIPAddr(net, raddr)
 	if err != nil {
-		t.Errorf("ResolveIPAddr(%#q, %#q) failed: %v", net, raddr, err)
+		t.Errorf("ResolveIPAddr(%q, %q) failed: %v", net, raddr, err)
 		return
 	}
 
 	waitForReady := make(chan bool)
-	go icmpEchoTransponder(t, net, raddr, ipv6, waitForReady)
+	go icmpEchoTransponder(t, net, raddr, waitForReady)
 	<-waitForReady
 
 	_, err = c.WriteTo(echo, ra)
@@ -71,11 +72,15 @@ func exchangeICMPEcho(t *testing.T, net, laddr, raddr string, ipv6 bool, echo []
 			t.Errorf("ReadFrom failed: %v", err)
 			return
 		}
-		if !ipv6 && reply[0] != ICMP4_ECHO_REPLY {
-			continue
-		}
-		if ipv6 && reply[0] != ICMP6_ECHO_REPLY {
-			continue
+		switch c.(*IPConn).fd.family {
+		case syscall.AF_INET:
+			if reply[0] != ICMP4_ECHO_REPLY {
+				continue
+			}
+		case syscall.AF_INET6:
+			if reply[0] != ICMP6_ECHO_REPLY {
+				continue
+			}
 		}
 		xid, xseqnum := parseICMPEchoReply(echo)
 		rid, rseqnum := parseICMPEchoReply(reply)
@@ -87,11 +92,11 @@ func exchangeICMPEcho(t *testing.T, net, laddr, raddr string, ipv6 bool, echo []
 	}
 }
 
-func icmpEchoTransponder(t *testing.T, net, raddr string, ipv6 bool, waitForReady chan bool) {
+func icmpEchoTransponder(t *testing.T, net, raddr string, waitForReady chan bool) {
 	c, err := Dial(net, raddr)
 	if err != nil {
 		waitForReady <- true
-		t.Errorf("Dial(%#q, %#q) failed: %v", net, raddr, err)
+		t.Errorf("Dial(%q, %q) failed: %v", net, raddr, err)
 		return
 	}
 	c.SetDeadline(time.Now().Add(100 * time.Millisecond))
@@ -106,18 +111,23 @@ func icmpEchoTransponder(t *testing.T, net, raddr string, ipv6 bool, waitForRead
 			t.Errorf("Read failed: %v", err)
 			return
 		}
-		if !ipv6 && echo[0] != ICMP4_ECHO_REQUEST {
-			continue
-		}
-		if ipv6 && echo[0] != ICMP6_ECHO_REQUEST {
-			continue
+		switch c.(*IPConn).fd.family {
+		case syscall.AF_INET:
+			if echo[0] != ICMP4_ECHO_REQUEST {
+				continue
+			}
+		case syscall.AF_INET6:
+			if echo[0] != ICMP6_ECHO_REQUEST {
+				continue
+			}
 		}
 		break
 	}
 
-	if !ipv6 {
+	switch c.(*IPConn).fd.family {
+	case syscall.AF_INET:
 		echo[0] = ICMP4_ECHO_REPLY
-	} else {
+	case syscall.AF_INET6:
 		echo[0] = ICMP6_ECHO_REPLY
 	}
 
@@ -135,11 +145,15 @@ const (
 	ICMP6_ECHO_REPLY   = 129
 )
 
-func newICMPEchoRequest(ipv6 bool, id, seqnum, msglen int, filler []byte) []byte {
-	if !ipv6 {
+func newICMPEchoRequest(net string, id, seqnum, msglen int, filler []byte) []byte {
+	afnet, _, _ := parseDialNetwork(net)
+	switch afnet {
+	case "ip4":
 		return newICMPv4EchoRequest(id, seqnum, msglen, filler)
+	case "ip6":
+		return newICMPv6EchoRequest(id, seqnum, msglen, filler)
 	}
-	return newICMPv6EchoRequest(id, seqnum, msglen, filler)
+	return nil
 }
 
 func newICMPv4EchoRequest(id, seqnum, msglen int, filler []byte) []byte {
diff --git a/libgo/go/net/iprawsock_plan9.go b/libgo/go/net/iprawsock_plan9.go
index 382a4402770..43719fc99cd 100644
--- a/libgo/go/net/iprawsock_plan9.go
+++ b/libgo/go/net/iprawsock_plan9.go
@@ -7,7 +7,7 @@
 package net
 
 import (
-	"os"
+	"syscall"
 	"time"
 )
 
@@ -17,34 +17,34 @@ type IPConn bool
 
 // SetDeadline implements the Conn SetDeadline method.
 func (c *IPConn) SetDeadline(t time.Time) error {
-	return os.EPLAN9
+	return syscall.EPLAN9
 }
 
 // SetReadDeadline implements the Conn SetReadDeadline method.
 func (c *IPConn) SetReadDeadline(t time.Time) error {
-	return os.EPLAN9
+	return syscall.EPLAN9
 }
 
 // SetWriteDeadline implements the Conn SetWriteDeadline method.
 func (c *IPConn) SetWriteDeadline(t time.Time) error {
-	return os.EPLAN9
+	return syscall.EPLAN9
 }
 
 // Implementation of the Conn interface - see Conn for documentation.
 
 // Read implements the Conn Read method.
 func (c *IPConn) Read(b []byte) (int, error) {
-	return 0, os.EPLAN9
+	return 0, syscall.EPLAN9
 }
 
 // Write implements the Conn Write method.
 func (c *IPConn) Write(b []byte) (int, error) {
-	return 0, os.EPLAN9
+	return 0, syscall.EPLAN9
 }
 
 // Close closes the IP connection.
 func (c *IPConn) Close() error {
-	return os.EPLAN9
+	return syscall.EPLAN9
 }
 
 // LocalAddr returns the local network address.
@@ -67,12 +67,12 @@ func (c *IPConn) RemoteAddr() Addr {
 // Timeout() == true after a fixed time limit; see SetDeadline and
 // SetReadDeadline.
 func (c *IPConn) ReadFromIP(b []byte) (int, *IPAddr, error) {
-	return 0, nil, os.EPLAN9
+	return 0, nil, syscall.EPLAN9
 }
 
 // ReadFrom implements the PacketConn ReadFrom method.
 func (c *IPConn) ReadFrom(b []byte) (int, Addr, error) {
-	return 0, nil, os.EPLAN9
+	return 0, nil, syscall.EPLAN9
 }
 
 // WriteToIP writes a IP packet to addr via c, copying the payload from b.
@@ -82,18 +82,18 @@ func (c *IPConn) ReadFrom(b []byte) (int, Addr, error) {
 // see SetDeadline and SetWriteDeadline.
 // On packet-oriented connections, write timeouts are rare.
 func (c *IPConn) WriteToIP(b []byte, addr *IPAddr) (int, error) {
-	return 0, os.EPLAN9
+	return 0, syscall.EPLAN9
 }
 
 // WriteTo implements the PacketConn WriteTo method.
 func (c *IPConn) WriteTo(b []byte, addr Addr) (int, error) {
-	return 0, os.EPLAN9
+	return 0, syscall.EPLAN9
 }
 
 // DialIP connects to the remote address raddr on the network protocol netProto,
 // which must be "ip", "ip4", or "ip6" followed by a colon and a protocol number or name.
 func DialIP(netProto string, laddr, raddr *IPAddr) (*IPConn, error) {
-	return nil, os.EPLAN9
+	return nil, syscall.EPLAN9
 }
 
 // ListenIP listens for incoming IP packets addressed to the
@@ -101,5 +101,5 @@ func DialIP(netProto string, laddr, raddr *IPAddr) (*IPConn, error) {
 // and WriteTo methods can be used to receive and send IP
 // packets with per-packet addressing.
 func ListenIP(netProto string, laddr *IPAddr) (*IPConn, error) {
-	return nil, os.EPLAN9
+	return nil, syscall.EPLAN9
 }
diff --git a/libgo/go/net/iprawsock_posix.go b/libgo/go/net/iprawsock_posix.go
index c34ffeb121d..9caa86985a5 100644
--- a/libgo/go/net/iprawsock_posix.go
+++ b/libgo/go/net/iprawsock_posix.go
@@ -66,7 +66,7 @@ func (c *IPConn) Read(b []byte) (int, error) {
 // Write implements the Conn Write method.
 func (c *IPConn) Write(b []byte) (int, error) {
 	if !c.ok() {
-		return 0, os.EINVAL
+		return 0, syscall.EINVAL
 	}
 	return c.fd.Write(b)
 }
@@ -74,7 +74,7 @@ func (c *IPConn) Write(b []byte) (int, error) {
 // Close closes the IP connection.
 func (c *IPConn) Close() error {
 	if !c.ok() {
-		return os.EINVAL
+		return syscall.EINVAL
 	}
 	err := c.fd.Close()
 	c.fd = nil
@@ -100,7 +100,7 @@ func (c *IPConn) RemoteAddr() Addr {
 // SetDeadline implements the Conn SetDeadline method.
 func (c *IPConn) SetDeadline(t time.Time) error {
 	if !c.ok() {
-		return os.EINVAL
+		return syscall.EINVAL
 	}
 	return setDeadline(c.fd, t)
 }
@@ -108,7 +108,7 @@ func (c *IPConn) SetDeadline(t time.Time) error {
 // SetReadDeadline implements the Conn SetReadDeadline method.
 func (c *IPConn) SetReadDeadline(t time.Time) error {
 	if !c.ok() {
-		return os.EINVAL
+		return syscall.EINVAL
 	}
 	return setReadDeadline(c.fd, t)
 }
@@ -116,7 +116,7 @@ func (c *IPConn) SetReadDeadline(t time.Time) error {
 // SetWriteDeadline implements the Conn SetWriteDeadline method.
 func (c *IPConn) SetWriteDeadline(t time.Time) error {
 	if !c.ok() {
-		return os.EINVAL
+		return syscall.EINVAL
 	}
 	return setWriteDeadline(c.fd, t)
 }
@@ -125,7 +125,7 @@ func (c *IPConn) SetWriteDeadline(t time.Time) error {
 // receive buffer associated with the connection.
 func (c *IPConn) SetReadBuffer(bytes int) error {
 	if !c.ok() {
-		return os.EINVAL
+		return syscall.EINVAL
 	}
 	return setReadBuffer(c.fd, bytes)
 }
@@ -134,7 +134,7 @@ func (c *IPConn) SetReadBuffer(bytes int) error {
 // transmit buffer associated with the connection.
 func (c *IPConn) SetWriteBuffer(bytes int) error {
 	if !c.ok() {
-		return os.EINVAL
+		return syscall.EINVAL
 	}
 	return setWriteBuffer(c.fd, bytes)
 }
@@ -150,7 +150,7 @@ func (c *IPConn) SetWriteBuffer(bytes int) error {
 // SetReadDeadline.
 func (c *IPConn) ReadFromIP(b []byte) (int, *IPAddr, error) {
 	if !c.ok() {
-		return 0, nil, os.EINVAL
+		return 0, nil, syscall.EINVAL
 	}
 	// TODO(cw,rsc): consider using readv if we know the family
 	// type to avoid the header trim/copy
@@ -173,7 +173,7 @@ func (c *IPConn) ReadFromIP(b []byte) (int, *IPAddr, error) {
 // ReadFrom implements the PacketConn ReadFrom method.
 func (c *IPConn) ReadFrom(b []byte) (int, Addr, error) {
 	if !c.ok() {
-		return 0, nil, os.EINVAL
+		return 0, nil, syscall.EINVAL
 	}
 	n, uaddr, err := c.ReadFromIP(b)
 	return n, uaddr.toAddr(), err
@@ -187,7 +187,7 @@ func (c *IPConn) ReadFrom(b []byte) (int, Addr, error) {
 // On packet-oriented connections, write timeouts are rare.
 func (c *IPConn) WriteToIP(b []byte, addr *IPAddr) (int, error) {
 	if !c.ok() {
-		return 0, os.EINVAL
+		return 0, syscall.EINVAL
 	}
 	sa, err := addr.sockaddr(c.fd.family)
 	if err != nil {
@@ -199,11 +199,11 @@ func (c *IPConn) WriteToIP(b []byte, addr *IPAddr) (int, error) {
 // WriteTo implements the PacketConn WriteTo method.
 func (c *IPConn) WriteTo(b []byte, addr Addr) (int, error) {
 	if !c.ok() {
-		return 0, os.EINVAL
+		return 0, syscall.EINVAL
 	}
 	a, ok := addr.(*IPAddr)
 	if !ok {
-		return 0, &OpError{"write", c.fd.net, addr, os.EINVAL}
+		return 0, &OpError{"write", c.fd.net, addr, syscall.EINVAL}
 	}
 	return c.WriteToIP(b, a)
 }
diff --git a/libgo/go/net/ipsock_plan9.go b/libgo/go/net/ipsock_plan9.go
index 597b1277544..eab0bf3e899 100644
--- a/libgo/go/net/ipsock_plan9.go
+++ b/libgo/go/net/ipsock_plan9.go
@@ -10,6 +10,7 @@ import (
 	"errors"
 	"io"
 	"os"
+	"syscall"
 	"time"
 )
 
@@ -83,7 +84,7 @@ func (c *plan9Conn) ok() bool { return c != nil && c.ctl != nil }
 // Read implements the Conn Read method.
 func (c *plan9Conn) Read(b []byte) (n int, err error) {
 	if !c.ok() {
-		return 0, os.EINVAL
+		return 0, syscall.EINVAL
 	}
 	if c.data == nil {
 		c.data, err = os.OpenFile(c.dir+"/data", os.O_RDWR, 0)
@@ -102,7 +103,7 @@ func (c *plan9Conn) Read(b []byte) (n int, err error) {
 // Write implements the Conn Write method.
 func (c *plan9Conn) Write(b []byte) (n int, err error) {
 	if !c.ok() {
-		return 0, os.EINVAL
+		return 0, syscall.EINVAL
 	}
 	if c.data == nil {
 		c.data, err = os.OpenFile(c.dir+"/data", os.O_RDWR, 0)
@@ -116,7 +117,7 @@ func (c *plan9Conn) Write(b []byte) (n int, err error) {
 // Close closes the connection.
 func (c *plan9Conn) Close() error {
 	if !c.ok() {
-		return os.EINVAL
+		return syscall.EINVAL
 	}
 	err := c.ctl.Close()
 	if err != nil {
@@ -148,17 +149,17 @@ func (c *plan9Conn) RemoteAddr() Addr {
 
 // SetDeadline implements the Conn SetDeadline method.
 func (c *plan9Conn) SetDeadline(t time.Time) error {
-	return os.EPLAN9
+	return syscall.EPLAN9
 }
 
 // SetReadDeadline implements the Conn SetReadDeadline method.
 func (c *plan9Conn) SetReadDeadline(t time.Time) error {
-	return os.EPLAN9
+	return syscall.EPLAN9
 }
 
 // SetWriteDeadline implements the Conn SetWriteDeadline method.
 func (c *plan9Conn) SetWriteDeadline(t time.Time) error {
-	return os.EPLAN9
+	return syscall.EPLAN9
 }
 
 func startPlan9(net string, addr Addr) (ctl *os.File, dest, proto, name string, err error) {
@@ -280,7 +281,7 @@ func (l *plan9Listener) Accept() (c Conn, err error) {
 
 func (l *plan9Listener) Close() error {
 	if l == nil || l.ctl == nil {
-		return os.EINVAL
+		return syscall.EINVAL
 	}
 	return l.ctl.Close()
 }
diff --git a/libgo/go/net/ipsock_posix.go b/libgo/go/net/ipsock_posix.go
index 4da18a5061a..4841057d6be 100644
--- a/libgo/go/net/ipsock_posix.go
+++ b/libgo/go/net/ipsock_posix.go
@@ -105,21 +105,20 @@ type sockaddr interface {
 }
 
 func internetSocket(net string, laddr, raddr sockaddr, sotype, proto int, mode string, toAddr func(syscall.Sockaddr) Addr) (fd *netFD, err error) {
-	var oserr error
 	var la, ra syscall.Sockaddr
 	family := favoriteAddrFamily(net, laddr, raddr, mode)
 	if laddr != nil {
-		if la, oserr = laddr.sockaddr(family); oserr != nil {
+		if la, err = laddr.sockaddr(family); err != nil {
 			goto Error
 		}
 	}
 	if raddr != nil {
-		if ra, oserr = raddr.sockaddr(family); oserr != nil {
+		if ra, err = raddr.sockaddr(family); err != nil {
 			goto Error
 		}
 	}
-	fd, oserr = socket(net, family, sotype, proto, la, ra, toAddr)
-	if oserr != nil {
+	fd, err = socket(net, family, sotype, proto, la, ra, toAddr)
+	if err != nil {
 		goto Error
 	}
 	return fd, nil
@@ -129,7 +128,7 @@ Error:
 	if mode == "listen" {
 		addr = laddr
 	}
-	return nil, &OpError{mode, net, addr, oserr}
+	return nil, &OpError{mode, net, addr, err}
 }
 
 func ipToSockaddr(family int, ip IP, port int) (syscall.Sockaddr, error) {
diff --git a/libgo/go/net/lookup_plan9.go b/libgo/go/net/lookup_plan9.go
index c0bb9225a7d..b08a9fb98e0 100644
--- a/libgo/go/net/lookup_plan9.go
+++ b/libgo/go/net/lookup_plan9.go
@@ -7,6 +7,7 @@ package net
 import (
 	"errors"
 	"os"
+	"syscall"
 )
 
 func query(filename, query string, bufSize int) (res []string, err error) {
@@ -71,7 +72,7 @@ func queryDNS(addr string, typ string) (res []string, err error) {
 
 func lookupProtocol(name string) (proto int, err error) {
 	// TODO: Implement this
-	return 0, os.EPLAN9
+	return 0, syscall.EPLAN9
 }
 
 func lookupHost(host string) (addrs []string, err error) {
diff --git a/libgo/go/net/lookup_test.go b/libgo/go/net/lookup_test.go
index 9a39ca8a1eb..7b9ea844cd4 100644
--- a/libgo/go/net/lookup_test.go
+++ b/libgo/go/net/lookup_test.go
@@ -8,14 +8,14 @@
 package net
 
 import (
-	"runtime"
+	"flag"
 	"testing"
 )
 
-var avoidMacFirewall = runtime.GOOS == "darwin"
+var testExternal = flag.Bool("external", false, "allow use of external networks during test")
 
 func TestGoogleSRV(t *testing.T) {
-	if testing.Short() || avoidMacFirewall {
+	if testing.Short() || !*testExternal {
 		t.Logf("skipping test to avoid external network")
 		return
 	}
@@ -38,7 +38,7 @@ func TestGoogleSRV(t *testing.T) {
 }
 
 func TestGmailMX(t *testing.T) {
-	if testing.Short() || avoidMacFirewall {
+	if testing.Short() || !*testExternal {
 		t.Logf("skipping test to avoid external network")
 		return
 	}
@@ -52,7 +52,7 @@ func TestGmailMX(t *testing.T) {
 }
 
 func TestGmailTXT(t *testing.T) {
-	if testing.Short() || avoidMacFirewall {
+	if testing.Short() || !*testExternal {
 		t.Logf("skipping test to avoid external network")
 		return
 	}
@@ -66,7 +66,7 @@ func TestGmailTXT(t *testing.T) {
 }
 
 func TestGoogleDNSAddr(t *testing.T) {
-	if testing.Short() || avoidMacFirewall {
+	if testing.Short() || !*testExternal {
 		t.Logf("skipping test to avoid external network")
 		return
 	}
diff --git a/libgo/go/net/multicast_test.go b/libgo/go/net/multicast_test.go
index f62580de66e..1d760c21051 100644
--- a/libgo/go/net/multicast_test.go
+++ b/libgo/go/net/multicast_test.go
@@ -5,30 +5,46 @@
 package net
 
 import (
+	"errors"
 	"os"
 	"runtime"
+	"syscall"
 	"testing"
 )
 
-var listenMulticastUDPTests = []struct {
+var multicastListenerTests = []struct {
 	net   string
 	gaddr *UDPAddr
 	flags Flags
-	ipv6  bool
+	ipv6  bool // test with underlying AF_INET6 socket
 }{
 	// cf. RFC 4727: Experimental Values in IPv4, IPv6, ICMPv4, ICMPv6, UDP, and TCP Headers
+
 	{"udp", &UDPAddr{IPv4(224, 0, 0, 254), 12345}, FlagUp | FlagLoopback, false},
-	{"udp4", &UDPAddr{IPv4(224, 0, 0, 254), 12345}, FlagUp | FlagLoopback, false},
+	{"udp", &UDPAddr{IPv4(224, 0, 0, 254), 12345}, 0, false},
 	{"udp", &UDPAddr{ParseIP("ff0e::114"), 12345}, FlagUp | FlagLoopback, true},
+	{"udp", &UDPAddr{ParseIP("ff0e::114"), 12345}, 0, true},
+
+	{"udp4", &UDPAddr{IPv4(224, 0, 0, 254), 12345}, FlagUp | FlagLoopback, false},
+	{"udp4", &UDPAddr{IPv4(224, 0, 0, 254), 12345}, 0, false},
+
 	{"udp6", &UDPAddr{ParseIP("ff01::114"), 12345}, FlagUp | FlagLoopback, true},
+	{"udp6", &UDPAddr{ParseIP("ff01::114"), 12345}, 0, true},
 	{"udp6", &UDPAddr{ParseIP("ff02::114"), 12345}, FlagUp | FlagLoopback, true},
+	{"udp6", &UDPAddr{ParseIP("ff02::114"), 12345}, 0, true},
 	{"udp6", &UDPAddr{ParseIP("ff04::114"), 12345}, FlagUp | FlagLoopback, true},
+	{"udp6", &UDPAddr{ParseIP("ff04::114"), 12345}, 0, true},
 	{"udp6", &UDPAddr{ParseIP("ff05::114"), 12345}, FlagUp | FlagLoopback, true},
+	{"udp6", &UDPAddr{ParseIP("ff05::114"), 12345}, 0, true},
 	{"udp6", &UDPAddr{ParseIP("ff08::114"), 12345}, FlagUp | FlagLoopback, true},
+	{"udp6", &UDPAddr{ParseIP("ff08::114"), 12345}, 0, true},
 	{"udp6", &UDPAddr{ParseIP("ff0e::114"), 12345}, FlagUp | FlagLoopback, true},
+	{"udp6", &UDPAddr{ParseIP("ff0e::114"), 12345}, 0, true},
 }
 
-func TestListenMulticastUDP(t *testing.T) {
+// TestMulticastListener tests both single and double listen to a test
+// listener with same address family, same group address and same port.
+func TestMulticastListener(t *testing.T) {
 	switch runtime.GOOS {
 	case "netbsd", "openbsd", "plan9", "windows":
 		return
@@ -38,112 +54,142 @@ func TestListenMulticastUDP(t *testing.T) {
 		}
 	}
 
-	for _, tt := range listenMulticastUDPTests {
+	for _, tt := range multicastListenerTests {
 		if tt.ipv6 && (!supportsIPv6 || os.Getuid() != 0) {
 			continue
 		}
-		ift, err := Interfaces()
+		ifi, err := availMulticastInterface(t, tt.flags)
 		if err != nil {
-			t.Fatalf("Interfaces failed: %v", err)
-		}
-		var ifi *Interface
-		for _, x := range ift {
-			if x.Flags&tt.flags == tt.flags {
-				ifi = &x
-				break
-			}
-		}
-		if ifi == nil {
-			t.Logf("an appropriate multicast interface not found")
-			return
+			continue
 		}
-		c, err := ListenMulticastUDP(tt.net, ifi, tt.gaddr)
+		c1, err := ListenMulticastUDP(tt.net, ifi, tt.gaddr)
 		if err != nil {
-			t.Fatalf("ListenMulticastUDP failed: %v", err)
+			t.Fatalf("First ListenMulticastUDP failed: %v", err)
 		}
-		defer c.Close() // test to listen concurrently across multiple listeners
-		if !tt.ipv6 {
-			testIPv4MulticastSocketOptions(t, c.fd, ifi)
-		} else {
-			testIPv6MulticastSocketOptions(t, c.fd, ifi)
-		}
-		ifmat, err := ifi.MulticastAddrs()
+		checkMulticastListener(t, err, c1, tt.gaddr)
+		c2, err := ListenMulticastUDP(tt.net, ifi, tt.gaddr)
 		if err != nil {
-			t.Fatalf("MulticastAddrs failed: %v", err)
-		}
-		var found bool
-		for _, ifma := range ifmat {
-			if ifma.(*IPAddr).IP.Equal(tt.gaddr.IP) {
-				found = true
-				break
-			}
+			t.Fatalf("Second ListenMulticastUDP failed: %v", err)
 		}
-		if !found {
-			t.Fatalf("%q not found in RIB", tt.gaddr.String())
+		checkMulticastListener(t, err, c2, tt.gaddr)
+		c2.Close()
+		switch c1.fd.family {
+		case syscall.AF_INET:
+			testIPv4MulticastSocketOptions(t, c1.fd, ifi)
+		case syscall.AF_INET6:
+			testIPv6MulticastSocketOptions(t, c1.fd, ifi)
 		}
+		c1.Close()
 	}
 }
 
-func TestSimpleListenMulticastUDP(t *testing.T) {
+func TestSimpleMulticastListener(t *testing.T) {
 	switch runtime.GOOS {
 	case "plan9":
 		return
 	}
 
-	for _, tt := range listenMulticastUDPTests {
+	for _, tt := range multicastListenerTests {
 		if tt.ipv6 {
 			continue
 		}
-		tt.flags = FlagUp | FlagMulticast
+		tt.flags = FlagUp | FlagMulticast // for windows testing
+		ifi, err := availMulticastInterface(t, tt.flags)
+		if err != nil {
+			continue
+		}
+		c1, err := ListenMulticastUDP(tt.net, ifi, tt.gaddr)
+		if err != nil {
+			t.Fatalf("First ListenMulticastUDP failed: %v", err)
+		}
+		checkSimpleMulticastListener(t, err, c1, tt.gaddr)
+		c2, err := ListenMulticastUDP(tt.net, ifi, tt.gaddr)
+		if err != nil {
+			t.Fatalf("Second ListenMulticastUDP failed: %v", err)
+		}
+		checkSimpleMulticastListener(t, err, c2, tt.gaddr)
+		c2.Close()
+		c1.Close()
+	}
+}
+
+func checkMulticastListener(t *testing.T, err error, c *UDPConn, gaddr *UDPAddr) {
+	if !multicastRIBContains(t, gaddr.IP) {
+		t.Fatalf("%q not found in RIB", gaddr.String())
+	}
+	if c.LocalAddr().String() != gaddr.String() {
+		t.Fatalf("LocalAddr returns %q, expected %q", c.LocalAddr().String(), gaddr.String())
+	}
+}
+
+func checkSimpleMulticastListener(t *testing.T, err error, c *UDPConn, gaddr *UDPAddr) {
+	if c.LocalAddr().String() != gaddr.String() {
+		t.Fatalf("LocalAddr returns %q, expected %q", c.LocalAddr().String(), gaddr.String())
+	}
+}
+
+func availMulticastInterface(t *testing.T, flags Flags) (*Interface, error) {
+	var ifi *Interface
+	if flags != Flags(0) {
 		ift, err := Interfaces()
 		if err != nil {
 			t.Fatalf("Interfaces failed: %v", err)
 		}
-		var ifi *Interface
 		for _, x := range ift {
-			if x.Flags&tt.flags == tt.flags {
+			if x.Flags&flags == flags {
 				ifi = &x
 				break
 			}
 		}
 		if ifi == nil {
-			t.Logf("an appropriate multicast interface not found")
-			return
+			return nil, errors.New("an appropriate multicast interface not found")
 		}
-		c, err := ListenMulticastUDP(tt.net, ifi, tt.gaddr)
+	}
+	return ifi, nil
+}
+
+func multicastRIBContains(t *testing.T, ip IP) bool {
+	ift, err := Interfaces()
+	if err != nil {
+		t.Fatalf("Interfaces failed: %v", err)
+	}
+	for _, ifi := range ift {
+		ifmat, err := ifi.MulticastAddrs()
 		if err != nil {
-			t.Fatalf("ListenMulticastUDP failed: %v", err)
+			t.Fatalf("MulticastAddrs failed: %v", err)
+		}
+		for _, ifma := range ifmat {
+			if ifma.(*IPAddr).IP.Equal(ip) {
+				return true
+			}
 		}
-		c.Close()
 	}
+	return false
 }
 
 func testIPv4MulticastSocketOptions(t *testing.T, fd *netFD, ifi *Interface) {
-	ifmc, err := ipv4MulticastInterface(fd)
+	_, err := ipv4MulticastInterface(fd)
 	if err != nil {
 		t.Fatalf("ipv4MulticastInterface failed: %v", err)
 	}
-	t.Logf("IPv4 multicast interface: %v", ifmc)
-	err = setIPv4MulticastInterface(fd, ifi)
-	if err != nil {
-		t.Fatalf("setIPv4MulticastInterface failed: %v", err)
+	if ifi != nil {
+		err = setIPv4MulticastInterface(fd, ifi)
+		if err != nil {
+			t.Fatalf("setIPv4MulticastInterface failed: %v", err)
+		}
 	}
-
-	ttl, err := ipv4MulticastTTL(fd)
+	_, err = ipv4MulticastTTL(fd)
 	if err != nil {
 		t.Fatalf("ipv4MulticastTTL failed: %v", err)
 	}
-	t.Logf("IPv4 multicast TTL: %v", ttl)
 	err = setIPv4MulticastTTL(fd, 1)
 	if err != nil {
 		t.Fatalf("setIPv4MulticastTTL failed: %v", err)
 	}
-
-	loop, err := ipv4MulticastLoopback(fd)
+	_, err = ipv4MulticastLoopback(fd)
 	if err != nil {
 		t.Fatalf("ipv4MulticastLoopback failed: %v", err)
 	}
-	t.Logf("IPv4 multicast loopback: %v", loop)
 	err = setIPv4MulticastLoopback(fd, false)
 	if err != nil {
 		t.Fatalf("setIPv4MulticastLoopback failed: %v", err)
@@ -151,31 +197,28 @@ func testIPv4MulticastSocketOptions(t *testing.T, fd *netFD, ifi *Interface) {
 }
 
 func testIPv6MulticastSocketOptions(t *testing.T, fd *netFD, ifi *Interface) {
-	ifmc, err := ipv6MulticastInterface(fd)
+	_, err := ipv6MulticastInterface(fd)
 	if err != nil {
 		t.Fatalf("ipv6MulticastInterface failed: %v", err)
 	}
-	t.Logf("IPv6 multicast interface: %v", ifmc)
-	err = setIPv6MulticastInterface(fd, ifi)
-	if err != nil {
-		t.Fatalf("setIPv6MulticastInterface failed: %v", err)
+	if ifi != nil {
+		err = setIPv6MulticastInterface(fd, ifi)
+		if err != nil {
+			t.Fatalf("setIPv6MulticastInterface failed: %v", err)
+		}
 	}
-
-	hoplim, err := ipv6MulticastHopLimit(fd)
+	_, err = ipv6MulticastHopLimit(fd)
 	if err != nil {
 		t.Fatalf("ipv6MulticastHopLimit failed: %v", err)
 	}
-	t.Logf("IPv6 multicast hop limit: %v", hoplim)
 	err = setIPv6MulticastHopLimit(fd, 1)
 	if err != nil {
 		t.Fatalf("setIPv6MulticastHopLimit failed: %v", err)
 	}
-
-	loop, err := ipv6MulticastLoopback(fd)
+	_, err = ipv6MulticastLoopback(fd)
 	if err != nil {
 		t.Fatalf("ipv6MulticastLoopback failed: %v", err)
 	}
-	t.Logf("IPv6 multicast loopback: %v", loop)
 	err = setIPv6MulticastLoopback(fd, false)
 	if err != nil {
 		t.Fatalf("setIPv6MulticastLoopback failed: %v", err)
diff --git a/libgo/go/net/net.go b/libgo/go/net/net.go
index 79d36a2a813..bf242ff8dd6 100644
--- a/libgo/go/net/net.go
+++ b/libgo/go/net/net.go
@@ -2,8 +2,41 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// Package net provides a portable interface to Unix networks sockets,
-// including TCP/IP, UDP, domain name resolution, and Unix domain sockets.
+/*
+Package net provides a portable interface for network I/O, including
+TCP/IP, UDP, domain name resolution, and Unix domain sockets.
+
+Although the package provides access to low-level networking
+primitives, most clients will need only the basic interface provided
+by the Dial, Listen, and Accept functions and the associated
+Conn and Listener interfaces. The crypto/tls package uses
+the same interfaces and similar Dial and Listen functions.
+
+The Dial function connects to a server:
+
+	conn, err := net.Dial("tcp", "google.com:80")
+	if err != nil {
+		// handle error
+	}
+	fmt.Fprintf(conn, "GET / HTTP/1.0\r\n\r\n")
+	status, err := bufio.NewReader(conn).ReadString('\n')
+	// ...
+
+The Listen function creates servers:
+
+	ln, err := net.Listen("tcp", ":8080")
+	if err != nil {
+		// handle error
+	}
+	for {
+		conn, err := ln.Accept()
+		if err != nil {
+			// handle error
+			continue
+		}
+		go handleConnection(conn)
+	}
+*/
 package net
 
 // TODO(rsc):
@@ -42,21 +75,28 @@ type Conn interface {
 	RemoteAddr() Addr
 
 	// SetDeadline sets the read and write deadlines associated
-	// with the connection.
+	// with the connection. It is equivalent to calling both
+	// SetReadDeadline and SetWriteDeadline.
+	//
+	// A deadline is an absolute time after which I/O operations
+	// fail with a timeout (see type Error) instead of
+	// blocking. The deadline applies to all future I/O, not just
+	// the immediately following call to Read or Write.
+	//
+	// An idle timeout can be implemented by repeatedly extending
+	// the deadline after successful Read or Write calls.
+	//
+	// A zero value for t means I/O operations will not time out.
 	SetDeadline(t time.Time) error
 
-	// SetReadDeadline sets the deadline for all Read calls to return.
-	// If the deadline is reached, Read will fail with a timeout
-	// (see type Error) instead of blocking.
+	// SetReadDeadline sets the deadline for Read calls.
 	// A zero value for t means Read will not time out.
 	SetReadDeadline(t time.Time) error
 
-	// SetWriteDeadline sets the deadline for all Write calls to return.
-	// If the deadline is reached, Write will fail with a timeout
-	// (see type Error) instead of blocking.
-	// A zero value for t means Write will not time out.
+	// SetWriteDeadline sets the deadline for Write calls.
 	// Even if write times out, it may return n > 0, indicating that
 	// some of the data was successfully written.
+	// A zero value for t means Write will not time out.
 	SetWriteDeadline(t time.Time) error
 }
 
diff --git a/libgo/go/net/parse.go b/libgo/go/net/parse.go
index 4c4200a49b7..7c87b42f6d9 100644
--- a/libgo/go/net/parse.go
+++ b/libgo/go/net/parse.go
@@ -67,7 +67,7 @@ func open(name string) (*file, error) {
 	if err != nil {
 		return nil, err
 	}
-	return &file{fd, make([]byte, 1024)[0:0], false}, nil
+	return &file{fd, make([]byte, os.Getpagesize())[0:0], false}, nil
 }
 
 func byteIndex(s string, c byte) int {
diff --git a/libgo/go/net/rpc/server_test.go b/libgo/go/net/rpc/server_test.go
index 8cfa033ccc3..62c7b1e6004 100644
--- a/libgo/go/net/rpc/server_test.go
+++ b/libgo/go/net/rpc/server_test.go
@@ -387,12 +387,12 @@ func (WriteFailCodec) WriteRequest(*Request, interface{}) error {
 }
 
 func (WriteFailCodec) ReadResponseHeader(*Response) error {
-	time.Sleep(120 * time.Second)
+	select {}
 	panic("unreachable")
 }
 
 func (WriteFailCodec) ReadResponseBody(interface{}) error {
-	time.Sleep(120 * time.Second)
+	select {}
 	panic("unreachable")
 }
 
diff --git a/libgo/go/net/server_test.go b/libgo/go/net/server_test.go
index 55691493aa9..b9862168153 100644
--- a/libgo/go/net/server_test.go
+++ b/libgo/go/net/server_test.go
@@ -95,7 +95,7 @@ func doTest(t *testing.T, network, listenaddr, dialaddr string) {
 	t.Logf("Test %q %q %q", network, listenaddr, dialaddr)
 	switch listenaddr {
 	case "", "0.0.0.0", "[::]", "[::ffff:0.0.0.0]":
-		if testing.Short() || avoidMacFirewall {
+		if testing.Short() || !*testExternal {
 			t.Logf("skip wildcard listen during short test")
 			return
 		}
diff --git a/libgo/go/net/smtp/smtp.go b/libgo/go/net/smtp/smtp.go
index f600cc86482..59f6449f0ab 100644
--- a/libgo/go/net/smtp/smtp.go
+++ b/libgo/go/net/smtp/smtp.go
@@ -50,15 +50,14 @@ func Dial(addr string) (*Client, error) {
 // server name to be used when authenticating.
 func NewClient(conn net.Conn, host string) (*Client, error) {
 	text := textproto.NewConn(conn)
-	_, msg, err := text.ReadResponse(220)
+	_, _, err := text.ReadResponse(220)
 	if err != nil {
 		text.Close()
 		return nil, err
 	}
 	c := &Client{Text: text, conn: conn, serverName: host}
-	if strings.Contains(msg, "ESMTP") {
-		err = c.ehlo()
-	} else {
+	err = c.ehlo()
+	if err != nil {
 		err = c.helo()
 	}
 	return c, err
diff --git a/libgo/go/net/smtp/smtp_test.go b/libgo/go/net/smtp/smtp_test.go
index ce887820531..c315d185c9d 100644
--- a/libgo/go/net/smtp/smtp_test.go
+++ b/libgo/go/net/smtp/smtp_test.go
@@ -8,9 +8,11 @@ import (
 	"bufio"
 	"bytes"
 	"io"
+	"net"
 	"net/textproto"
 	"strings"
 	"testing"
+	"time"
 )
 
 type authTest struct {
@@ -59,9 +61,12 @@ type faker struct {
 	io.ReadWriter
 }
 
-func (f faker) Close() error {
-	return nil
-}
+func (f faker) Close() error                     { return nil }
+func (f faker) LocalAddr() net.Addr              { return nil }
+func (f faker) RemoteAddr() net.Addr             { return nil }
+func (f faker) SetDeadline(time.Time) error      { return nil }
+func (f faker) SetReadDeadline(time.Time) error  { return nil }
+func (f faker) SetWriteDeadline(time.Time) error { return nil }
 
 func TestBasic(t *testing.T) {
 	basicServer = strings.Join(strings.Split(basicServer, "\n"), "\r\n")
@@ -180,3 +185,87 @@ Goodbye.
 .
 QUIT
 `
+
+func TestNewClient(t *testing.T) {
+	newClientServer = strings.Join(strings.Split(newClientServer, "\n"), "\r\n")
+	newClientClient = strings.Join(strings.Split(newClientClient, "\n"), "\r\n")
+
+	var cmdbuf bytes.Buffer
+	bcmdbuf := bufio.NewWriter(&cmdbuf)
+	out := func() string {
+		bcmdbuf.Flush()
+		return cmdbuf.String()
+	}
+	var fake faker
+	fake.ReadWriter = bufio.NewReadWriter(bufio.NewReader(strings.NewReader(newClientServer)), bcmdbuf)
+	c, err := NewClient(fake, "fake.host")
+	if err != nil {
+		t.Fatalf("NewClient: %v\n(after %v)", err, out())
+	}
+	if ok, args := c.Extension("aUtH"); !ok || args != "LOGIN PLAIN" {
+		t.Fatalf("Expected AUTH supported")
+	}
+	if ok, _ := c.Extension("DSN"); ok {
+		t.Fatalf("Shouldn't support DSN")
+	}
+	if err := c.Quit(); err != nil {
+		t.Fatalf("QUIT failed: %s", err)
+	}
+
+	actualcmds := out()
+	if newClientClient != actualcmds {
+		t.Fatalf("Got:\n%s\nExpected:\n%s", actualcmds, newClientClient)
+	}
+}
+
+var newClientServer = `220 hello world
+250-mx.google.com at your service
+250-SIZE 35651584
+250-AUTH LOGIN PLAIN
+250 8BITMIME
+221 OK
+`
+
+var newClientClient = `EHLO localhost
+QUIT
+`
+
+func TestNewClient2(t *testing.T) {
+	newClient2Server = strings.Join(strings.Split(newClient2Server, "\n"), "\r\n")
+	newClient2Client = strings.Join(strings.Split(newClient2Client, "\n"), "\r\n")
+
+	var cmdbuf bytes.Buffer
+	bcmdbuf := bufio.NewWriter(&cmdbuf)
+	var fake faker
+	fake.ReadWriter = bufio.NewReadWriter(bufio.NewReader(strings.NewReader(newClient2Server)), bcmdbuf)
+	c, err := NewClient(fake, "fake.host")
+	if err != nil {
+		t.Fatalf("NewClient: %v", err)
+	}
+	if ok, _ := c.Extension("DSN"); ok {
+		t.Fatalf("Shouldn't support DSN")
+	}
+	if err := c.Quit(); err != nil {
+		t.Fatalf("QUIT failed: %s", err)
+	}
+
+	bcmdbuf.Flush()
+	actualcmds := cmdbuf.String()
+	if newClient2Client != actualcmds {
+		t.Fatalf("Got:\n%s\nExpected:\n%s", actualcmds, newClient2Client)
+	}
+}
+
+var newClient2Server = `220 hello world
+502 EH?
+250-mx.google.com at your service
+250-SIZE 35651584
+250-AUTH LOGIN PLAIN
+250 8BITMIME
+221 OK
+`
+
+var newClient2Client = `EHLO localhost
+HELO localhost
+QUIT
+`
diff --git a/libgo/go/net/sock.go b/libgo/go/net/sock.go
index 70064c307ef..dc139f04a25 100644
--- a/libgo/go/net/sock.go
+++ b/libgo/go/net/sock.go
@@ -33,13 +33,14 @@ func socket(net string, f, t, p int, la, ra syscall.Sockaddr, toAddr func(syscal
 		return nil, err
 	}
 
+	var bla syscall.Sockaddr
 	if la != nil {
-		la, err = listenerSockaddr(s, f, la, toAddr)
+		bla, err = listenerSockaddr(s, f, la, toAddr)
 		if err != nil {
 			closesocket(s)
 			return nil, err
 		}
-		err = syscall.Bind(s, la)
+		err = syscall.Bind(s, bla)
 		if err != nil {
 			closesocket(s)
 			return nil, err
@@ -61,7 +62,12 @@ func socket(net string, f, t, p int, la, ra syscall.Sockaddr, toAddr func(syscal
 	}
 
 	sa, _ := syscall.Getsockname(s)
-	laddr := toAddr(sa)
+	var laddr Addr
+	if la != nil && bla != la {
+		laddr = toAddr(la)
+	} else {
+		laddr = toAddr(sa)
+	}
 	sa, _ = syscall.Getpeername(s)
 	raddr := toAddr(sa)
 
diff --git a/libgo/go/net/tcpsock_plan9.go b/libgo/go/net/tcpsock_plan9.go
index 128766144dd..35f56966eae 100644
--- a/libgo/go/net/tcpsock_plan9.go
+++ b/libgo/go/net/tcpsock_plan9.go
@@ -7,7 +7,7 @@
 package net
 
 import (
-	"os"
+	"syscall"
 	"time"
 )
 
@@ -19,35 +19,35 @@ type TCPConn struct {
 
 // SetDeadline implements the Conn SetDeadline method.
 func (c *TCPConn) SetDeadline(t time.Time) error {
-	return os.EPLAN9
+	return syscall.EPLAN9
 }
 
 // SetReadDeadline implements the Conn SetReadDeadline method.
 func (c *TCPConn) SetReadDeadline(t time.Time) error {
-	return os.EPLAN9
+	return syscall.EPLAN9
 }
 
 // SetWriteDeadline implements the Conn SetWriteDeadline method.
 func (c *TCPConn) SetWriteDeadline(t time.Time) error {
-	return os.EPLAN9
+	return syscall.EPLAN9
 }
 
 // CloseRead shuts down the reading side of the TCP connection.
 // Most callers should just use Close.
 func (c *TCPConn) CloseRead() error {
 	if !c.ok() {
-		return os.EINVAL
+		return syscall.EINVAL
 	}
-	return os.EPLAN9
+	return syscall.EPLAN9
 }
 
 // CloseWrite shuts down the writing side of the TCP connection.
 // Most callers should just use Close.
 func (c *TCPConn) CloseWrite() error {
 	if !c.ok() {
-		return os.EINVAL
+		return syscall.EINVAL
 	}
-	return os.EPLAN9
+	return syscall.EPLAN9
 }
 
 // DialTCP connects to the remote address raddr on the network net,
diff --git a/libgo/go/net/tcpsock_posix.go b/libgo/go/net/tcpsock_posix.go
index 200ce91566c..e05bc10170e 100644
--- a/libgo/go/net/tcpsock_posix.go
+++ b/libgo/go/net/tcpsock_posix.go
@@ -9,6 +9,7 @@
 package net
 
 import (
+	"fmt"
 	"io"
 	"os"
 	"syscall"
@@ -26,6 +27,11 @@ func sockaddrToTCP(sa syscall.Sockaddr) Addr {
 		return &TCPAddr{sa.Addr[0:], sa.Port}
 	case *syscall.SockaddrInet6:
 		return &TCPAddr{sa.Addr[0:], sa.Port}
+	default:
+		if sa != nil {
+			// Diagnose when we will turn a non-nil sockaddr into a nil.
+			panic(fmt.Sprintf("unexpected type in sockaddrToTCP: %T", sa))
+		}
 	}
 	return nil
 }
@@ -70,7 +76,7 @@ func (c *TCPConn) ok() bool { return c != nil && c.fd != nil }
 // Read implements the Conn Read method.
 func (c *TCPConn) Read(b []byte) (n int, err error) {
 	if !c.ok() {
-		return 0, os.EINVAL
+		return 0, syscall.EINVAL
 	}
 	return c.fd.Read(b)
 }
@@ -86,7 +92,7 @@ func (c *TCPConn) ReadFrom(r io.Reader) (int64, error) {
 // Write implements the Conn Write method.
 func (c *TCPConn) Write(b []byte) (n int, err error) {
 	if !c.ok() {
-		return 0, os.EINVAL
+		return 0, syscall.EINVAL
 	}
 	return c.fd.Write(b)
 }
@@ -94,7 +100,7 @@ func (c *TCPConn) Write(b []byte) (n int, err error) {
 // Close closes the TCP connection.
 func (c *TCPConn) Close() error {
 	if !c.ok() {
-		return os.EINVAL
+		return syscall.EINVAL
 	}
 	err := c.fd.Close()
 	c.fd = nil
@@ -105,7 +111,7 @@ func (c *TCPConn) Close() error {
 // Most callers should just use Close.
 func (c *TCPConn) CloseRead() error {
 	if !c.ok() {
-		return os.EINVAL
+		return syscall.EINVAL
 	}
 	return c.fd.CloseRead()
 }
@@ -114,7 +120,7 @@ func (c *TCPConn) CloseRead() error {
 // Most callers should just use Close.
 func (c *TCPConn) CloseWrite() error {
 	if !c.ok() {
-		return os.EINVAL
+		return syscall.EINVAL
 	}
 	return c.fd.CloseWrite()
 }
@@ -138,7 +144,7 @@ func (c *TCPConn) RemoteAddr() Addr {
 // SetDeadline implements the Conn SetDeadline method.
 func (c *TCPConn) SetDeadline(t time.Time) error {
 	if !c.ok() {
-		return os.EINVAL
+		return syscall.EINVAL
 	}
 	return setDeadline(c.fd, t)
 }
@@ -146,7 +152,7 @@ func (c *TCPConn) SetDeadline(t time.Time) error {
 // SetReadDeadline implements the Conn SetReadDeadline method.
 func (c *TCPConn) SetReadDeadline(t time.Time) error {
 	if !c.ok() {
-		return os.EINVAL
+		return syscall.EINVAL
 	}
 	return setReadDeadline(c.fd, t)
 }
@@ -154,7 +160,7 @@ func (c *TCPConn) SetReadDeadline(t time.Time) error {
 // SetWriteDeadline implements the Conn SetWriteDeadline method.
 func (c *TCPConn) SetWriteDeadline(t time.Time) error {
 	if !c.ok() {
-		return os.EINVAL
+		return syscall.EINVAL
 	}
 	return setWriteDeadline(c.fd, t)
 }
@@ -163,7 +169,7 @@ func (c *TCPConn) SetWriteDeadline(t time.Time) error {
 // receive buffer associated with the connection.
 func (c *TCPConn) SetReadBuffer(bytes int) error {
 	if !c.ok() {
-		return os.EINVAL
+		return syscall.EINVAL
 	}
 	return setReadBuffer(c.fd, bytes)
 }
@@ -172,7 +178,7 @@ func (c *TCPConn) SetReadBuffer(bytes int) error {
 // transmit buffer associated with the connection.
 func (c *TCPConn) SetWriteBuffer(bytes int) error {
 	if !c.ok() {
-		return os.EINVAL
+		return syscall.EINVAL
 	}
 	return setWriteBuffer(c.fd, bytes)
 }
@@ -190,7 +196,7 @@ func (c *TCPConn) SetWriteBuffer(bytes int) error {
 // data to be sent and acknowledged.
 func (c *TCPConn) SetLinger(sec int) error {
 	if !c.ok() {
-		return os.EINVAL
+		return syscall.EINVAL
 	}
 	return setLinger(c.fd, sec)
 }
@@ -199,7 +205,7 @@ func (c *TCPConn) SetLinger(sec int) error {
 // keepalive messages on the connection.
 func (c *TCPConn) SetKeepAlive(keepalive bool) error {
 	if !c.ok() {
-		return os.EINVAL
+		return syscall.EINVAL
 	}
 	return setKeepAlive(c.fd, keepalive)
 }
@@ -210,7 +216,7 @@ func (c *TCPConn) SetKeepAlive(keepalive bool) error {
 // that data is sent as soon as possible after a Write.
 func (c *TCPConn) SetNoDelay(noDelay bool) error {
 	if !c.ok() {
-		return os.EINVAL
+		return syscall.EINVAL
 	}
 	return setNoDelay(c.fd, noDelay)
 }
@@ -259,6 +265,17 @@ func DialTCP(net string, laddr, raddr *TCPAddr) (*TCPConn, error) {
 }
 
 func selfConnect(fd *netFD) bool {
+	// The socket constructor can return an fd with raddr nil under certain
+	// unknown conditions. The errors in the calls there to Getpeername
+	// are discarded, but we can't catch the problem there because those
+	// calls are sometimes legally erroneous with a "socket not connected".
+	// Since this code (selfConnect) is already trying to work around
+	// a problem, we make sure if this happens we recognize trouble and
+	// ask the DialTCP routine to try again.
+	// TODO: try to understand what's really going on.
+	if fd.laddr == nil || fd.raddr == nil {
+		return true
+	}
 	l := fd.laddr.(*TCPAddr)
 	r := fd.raddr.(*TCPAddr)
 	return l.Port == r.Port && l.IP.Equal(r.IP)
@@ -294,7 +311,7 @@ func ListenTCP(net string, laddr *TCPAddr) (*TCPListener, error) {
 // and the remote address.
 func (l *TCPListener) AcceptTCP() (c *TCPConn, err error) {
 	if l == nil || l.fd == nil || l.fd.sysfd < 0 {
-		return nil, os.EINVAL
+		return nil, syscall.EINVAL
 	}
 	fd, err := l.fd.accept(sockaddrToTCP)
 	if err != nil {
@@ -317,7 +334,7 @@ func (l *TCPListener) Accept() (c Conn, err error) {
 // Already Accepted connections are not closed.
 func (l *TCPListener) Close() error {
 	if l == nil || l.fd == nil {
-		return os.EINVAL
+		return syscall.EINVAL
 	}
 	return l.fd.Close()
 }
@@ -329,7 +346,7 @@ func (l *TCPListener) Addr() Addr { return l.fd.laddr }
 // A zero time value disables the deadline.
 func (l *TCPListener) SetDeadline(t time.Time) error {
 	if l == nil || l.fd == nil {
-		return os.EINVAL
+		return syscall.EINVAL
 	}
 	return setDeadline(l.fd, t)
 }
diff --git a/libgo/go/net/testdata/hosts b/libgo/go/net/testdata/hosts
new file mode 100644
index 00000000000..b601763898b
--- /dev/null
+++ b/libgo/go/net/testdata/hosts
@@ -0,0 +1,12 @@
+255.255.255.255	broadcasthost
+127.0.0.2	odin
+127.0.0.3	odin  # inline comment 
+::2             odin
+127.1.1.1	thor
+# aliases
+127.1.1.2	ullr ullrhost
+# Bogus entries that must be ignored.
+123.123.123	loki
+321.321.321.321
+# TODO(yvesj): Should we be able to parse this? From a Darwin system.
+fe80::1%lo0	localhost
diff --git a/libgo/go/net/testdata/igmp b/libgo/go/net/testdata/igmp
new file mode 100644
index 00000000000..5f380a2c7db
--- /dev/null
+++ b/libgo/go/net/testdata/igmp
@@ -0,0 +1,24 @@
+Idx	Device    : Count Querier	Group    Users Timer	Reporter
+1	lo        :     1      V3
+				010000E0     1 0:00000000		0
+2	eth0      :     2      V2
+				FB0000E0     1 0:00000000		1
+				010000E0     1 0:00000000		0
+3	eth1      :     1      V3
+				010000E0     1 0:00000000		0
+4	eth2      :     1      V3
+				010000E0     1 0:00000000		0
+5	eth0.100  :     2      V3
+				FB0000E0     1 0:00000000		0
+				010000E0     1 0:00000000		0
+6	eth0.101  :     2      V3
+				FB0000E0     1 0:00000000		0
+				010000E0     1 0:00000000		0
+7	eth0.102  :     2      V3
+				FB0000E0     1 0:00000000		0
+				010000E0     1 0:00000000		0
+8	eth0.103  :     2      V3
+				FB0000E0     1 0:00000000		0
+				010000E0     1 0:00000000		0
+9	device1tap2:     1      V3
+				010000E0     1 0:00000000		0
diff --git a/libgo/go/net/testdata/igmp6 b/libgo/go/net/testdata/igmp6
new file mode 100644
index 00000000000..6cd5a2d4d9d
--- /dev/null
+++ b/libgo/go/net/testdata/igmp6
@@ -0,0 +1,18 @@
+1    lo              ff020000000000000000000000000001     1 0000000C 0
+2    eth0            ff0200000000000000000001ffac891e     1 00000006 0
+2    eth0            ff020000000000000000000000000001     1 0000000C 0
+3    eth1            ff0200000000000000000001ffac8928     2 00000006 0
+3    eth1            ff020000000000000000000000000001     1 0000000C 0
+4    eth2            ff0200000000000000000001ffac8932     2 00000006 0
+4    eth2            ff020000000000000000000000000001     1 0000000C 0
+5    eth0.100        ff0200000000000000000001ffac891e     1 00000004 0
+5    eth0.100        ff020000000000000000000000000001     1 0000000C 0
+6    pan0            ff020000000000000000000000000001     1 0000000C 0
+7    eth0.101        ff0200000000000000000001ffac891e     1 00000004 0
+7    eth0.101        ff020000000000000000000000000001     1 0000000C 0
+8    eth0.102        ff0200000000000000000001ffac891e     1 00000004 0
+8    eth0.102        ff020000000000000000000000000001     1 0000000C 0
+9    eth0.103        ff0200000000000000000001ffac891e     1 00000004 0
+9    eth0.103        ff020000000000000000000000000001     1 0000000C 0
+10   device1tap2     ff0200000000000000000001ff4cc3a3     1 00000004 0
+10   device1tap2     ff020000000000000000000000000001     1 0000000C 0
diff --git a/libgo/go/net/textproto/reader.go b/libgo/go/net/textproto/reader.go
index 862cd536c46..125feb3e885 100644
--- a/libgo/go/net/textproto/reader.go
+++ b/libgo/go/net/textproto/reader.go
@@ -454,10 +454,14 @@ func (r *Reader) ReadMIMEHeader() (MIMEHeader, error) {
 
 		// Key ends at first colon; must not have spaces.
 		i := bytes.IndexByte(kv, ':')
-		if i < 0 || bytes.IndexByte(kv[0:i], ' ') >= 0 {
+		if i < 0 {
 			return m, ProtocolError("malformed MIME header line: " + string(kv))
 		}
-		key := CanonicalMIMEHeaderKey(string(kv[0:i]))
+		key := string(kv[0:i])
+		if strings.Index(key, " ") >= 0 {
+			key = strings.TrimRight(key, " ")
+		}
+		key = CanonicalMIMEHeaderKey(key)
 
 		// Skip initial spaces in value.
 		i++ // skip colon
@@ -503,6 +507,11 @@ MustRewrite:
 	a := []byte(s)
 	upper := true
 	for i, v := range a {
+		if v == ' ' {
+			a[i] = '-'
+			upper = true
+			continue
+		}
 		if upper && 'a' <= v && v <= 'z' {
 			a[i] = v + 'A' - 'a'
 		}
diff --git a/libgo/go/net/textproto/reader_test.go b/libgo/go/net/textproto/reader_test.go
index 4d036914801..7c5d16227ff 100644
--- a/libgo/go/net/textproto/reader_test.go
+++ b/libgo/go/net/textproto/reader_test.go
@@ -164,6 +164,29 @@ func TestLargeReadMIMEHeader(t *testing.T) {
 	}
 }
 
+// Test that we read slightly-bogus MIME headers seen in the wild,
+// with spaces before colons, and spaces in keys.
+func TestReadMIMEHeaderNonCompliant(t *testing.T) {
+	// Invalid HTTP response header as sent by an Axis security
+	// camera: (this is handled by IE, Firefox, Chrome, curl, etc.)
+	r := reader("Foo: bar\r\n" +
+		"Content-Language: en\r\n" +
+		"SID : 0\r\n" +
+		"Audio Mode : None\r\n" +
+		"Privilege : 127\r\n\r\n")
+	m, err := r.ReadMIMEHeader()
+	want := MIMEHeader{
+		"Foo":              {"bar"},
+		"Content-Language": {"en"},
+		"Sid":              {"0"},
+		"Audio-Mode":       {"None"},
+		"Privilege":        {"127"},
+	}
+	if !reflect.DeepEqual(m, want) || err != nil {
+		t.Fatalf("ReadMIMEHeader =\n%v, %v; want:\n%v", m, err, want)
+	}
+}
+
 type readResponseTest struct {
 	in       string
 	inCode   int
diff --git a/libgo/go/net/textproto/textproto.go b/libgo/go/net/textproto/textproto.go
index 317ec72b0cc..ad5840cf7da 100644
--- a/libgo/go/net/textproto/textproto.go
+++ b/libgo/go/net/textproto/textproto.go
@@ -20,6 +20,9 @@
 //
 // Writer, to write dot-encoded text blocks.
 //
+// Conn, a convenient packaging of Reader, Writer, and Pipeline for use
+// with a single network connection.
+//
 package textproto
 
 import (
diff --git a/libgo/go/net/udpsock_plan9.go b/libgo/go/net/udpsock_plan9.go
index f90a5fe9ab8..4f298a42f87 100644
--- a/libgo/go/net/udpsock_plan9.go
+++ b/libgo/go/net/udpsock_plan9.go
@@ -9,6 +9,7 @@ package net
 import (
 	"errors"
 	"os"
+	"syscall"
 	"time"
 )
 
@@ -20,17 +21,17 @@ type UDPConn struct {
 
 // SetDeadline implements the Conn SetDeadline method.
 func (c *UDPConn) SetDeadline(t time.Time) error {
-	return os.EPLAN9
+	return syscall.EPLAN9
 }
 
 // SetReadDeadline implements the Conn SetReadDeadline method.
 func (c *UDPConn) SetReadDeadline(t time.Time) error {
-	return os.EPLAN9
+	return syscall.EPLAN9
 }
 
 // SetWriteDeadline implements the Conn SetWriteDeadline method.
 func (c *UDPConn) SetWriteDeadline(t time.Time) error {
-	return os.EPLAN9
+	return syscall.EPLAN9
 }
 
 // UDP-specific methods.
@@ -43,7 +44,7 @@ func (c *UDPConn) SetWriteDeadline(t time.Time) error {
 // after a fixed time limit; see SetDeadline and SetReadDeadline.
 func (c *UDPConn) ReadFromUDP(b []byte) (n int, addr *UDPAddr, err error) {
 	if !c.ok() {
-		return 0, nil, os.EINVAL
+		return 0, nil, syscall.EINVAL
 	}
 	if c.data == nil {
 		c.data, err = os.OpenFile(c.dir+"/data", os.O_RDWR, 0)
@@ -69,7 +70,7 @@ func (c *UDPConn) ReadFromUDP(b []byte) (n int, addr *UDPAddr, err error) {
 // ReadFrom implements the PacketConn ReadFrom method.
 func (c *UDPConn) ReadFrom(b []byte) (n int, addr Addr, err error) {
 	if !c.ok() {
-		return 0, nil, os.EINVAL
+		return 0, nil, syscall.EINVAL
 	}
 	return c.ReadFromUDP(b)
 }
@@ -82,7 +83,7 @@ func (c *UDPConn) ReadFrom(b []byte) (n int, addr Addr, err error) {
 // On packet-oriented connections, write timeouts are rare.
 func (c *UDPConn) WriteToUDP(b []byte, addr *UDPAddr) (n int, err error) {
 	if !c.ok() {
-		return 0, os.EINVAL
+		return 0, syscall.EINVAL
 	}
 	if c.data == nil {
 		c.data, err = os.OpenFile(c.dir+"/data", os.O_RDWR, 0)
@@ -106,11 +107,11 @@ func (c *UDPConn) WriteToUDP(b []byte, addr *UDPAddr) (n int, err error) {
 // WriteTo implements the PacketConn WriteTo method.
 func (c *UDPConn) WriteTo(b []byte, addr Addr) (n int, err error) {
 	if !c.ok() {
-		return 0, os.EINVAL
+		return 0, syscall.EINVAL
 	}
 	a, ok := addr.(*UDPAddr)
 	if !ok {
-		return 0, &OpError{"write", c.dir, addr, os.EINVAL}
+		return 0, &OpError{"write", c.dir, addr, syscall.EINVAL}
 	}
 	return c.WriteToUDP(b, a)
 }
@@ -191,5 +192,5 @@ func ListenUDP(net string, laddr *UDPAddr) (c *UDPConn, err error) {
 // the interface to join.  ListenMulticastUDP uses default
 // multicast interface if ifi is nil.
 func ListenMulticastUDP(net string, ifi *Interface, gaddr *UDPAddr) (*UDPConn, error) {
-	return nil, os.EPLAN9
+	return nil, syscall.EPLAN9
 }
diff --git a/libgo/go/net/udpsock_posix.go b/libgo/go/net/udpsock_posix.go
index 6108373568a..1f99dc53867 100644
--- a/libgo/go/net/udpsock_posix.go
+++ b/libgo/go/net/udpsock_posix.go
@@ -63,7 +63,7 @@ func (c *UDPConn) ok() bool { return c != nil && c.fd != nil }
 // Read implements the Conn Read method.
 func (c *UDPConn) Read(b []byte) (int, error) {
 	if !c.ok() {
-		return 0, os.EINVAL
+		return 0, syscall.EINVAL
 	}
 	return c.fd.Read(b)
 }
@@ -71,7 +71,7 @@ func (c *UDPConn) Read(b []byte) (int, error) {
 // Write implements the Conn Write method.
 func (c *UDPConn) Write(b []byte) (int, error) {
 	if !c.ok() {
-		return 0, os.EINVAL
+		return 0, syscall.EINVAL
 	}
 	return c.fd.Write(b)
 }
@@ -79,7 +79,7 @@ func (c *UDPConn) Write(b []byte) (int, error) {
 // Close closes the UDP connection.
 func (c *UDPConn) Close() error {
 	if !c.ok() {
-		return os.EINVAL
+		return syscall.EINVAL
 	}
 	err := c.fd.Close()
 	c.fd = nil
@@ -105,7 +105,7 @@ func (c *UDPConn) RemoteAddr() Addr {
 // SetDeadline implements the Conn SetDeadline method.
 func (c *UDPConn) SetDeadline(t time.Time) error {
 	if !c.ok() {
-		return os.EINVAL
+		return syscall.EINVAL
 	}
 	return setDeadline(c.fd, t)
 }
@@ -113,7 +113,7 @@ func (c *UDPConn) SetDeadline(t time.Time) error {
 // SetReadDeadline implements the Conn SetReadDeadline method.
 func (c *UDPConn) SetReadDeadline(t time.Time) error {
 	if !c.ok() {
-		return os.EINVAL
+		return syscall.EINVAL
 	}
 	return setReadDeadline(c.fd, t)
 }
@@ -121,7 +121,7 @@ func (c *UDPConn) SetReadDeadline(t time.Time) error {
 // SetWriteDeadline implements the Conn SetWriteDeadline method.
 func (c *UDPConn) SetWriteDeadline(t time.Time) error {
 	if !c.ok() {
-		return os.EINVAL
+		return syscall.EINVAL
 	}
 	return setWriteDeadline(c.fd, t)
 }
@@ -130,7 +130,7 @@ func (c *UDPConn) SetWriteDeadline(t time.Time) error {
 // receive buffer associated with the connection.
 func (c *UDPConn) SetReadBuffer(bytes int) error {
 	if !c.ok() {
-		return os.EINVAL
+		return syscall.EINVAL
 	}
 	return setReadBuffer(c.fd, bytes)
 }
@@ -139,7 +139,7 @@ func (c *UDPConn) SetReadBuffer(bytes int) error {
 // transmit buffer associated with the connection.
 func (c *UDPConn) SetWriteBuffer(bytes int) error {
 	if !c.ok() {
-		return os.EINVAL
+		return syscall.EINVAL
 	}
 	return setWriteBuffer(c.fd, bytes)
 }
@@ -154,7 +154,7 @@ func (c *UDPConn) SetWriteBuffer(bytes int) error {
 // after a fixed time limit; see SetDeadline and SetReadDeadline.
 func (c *UDPConn) ReadFromUDP(b []byte) (n int, addr *UDPAddr, err error) {
 	if !c.ok() {
-		return 0, nil, os.EINVAL
+		return 0, nil, syscall.EINVAL
 	}
 	n, sa, err := c.fd.ReadFrom(b)
 	switch sa := sa.(type) {
@@ -169,7 +169,7 @@ func (c *UDPConn) ReadFromUDP(b []byte) (n int, addr *UDPAddr, err error) {
 // ReadFrom implements the PacketConn ReadFrom method.
 func (c *UDPConn) ReadFrom(b []byte) (int, Addr, error) {
 	if !c.ok() {
-		return 0, nil, os.EINVAL
+		return 0, nil, syscall.EINVAL
 	}
 	n, uaddr, err := c.ReadFromUDP(b)
 	return n, uaddr.toAddr(), err
@@ -183,7 +183,7 @@ func (c *UDPConn) ReadFrom(b []byte) (int, Addr, error) {
 // On packet-oriented connections, write timeouts are rare.
 func (c *UDPConn) WriteToUDP(b []byte, addr *UDPAddr) (int, error) {
 	if !c.ok() {
-		return 0, os.EINVAL
+		return 0, syscall.EINVAL
 	}
 	if c.fd.isConnected {
 		return 0, &OpError{"write", c.fd.net, addr, ErrWriteToConnected}
@@ -198,11 +198,11 @@ func (c *UDPConn) WriteToUDP(b []byte, addr *UDPAddr) (int, error) {
 // WriteTo implements the PacketConn WriteTo method.
 func (c *UDPConn) WriteTo(b []byte, addr Addr) (int, error) {
 	if !c.ok() {
-		return 0, os.EINVAL
+		return 0, syscall.EINVAL
 	}
 	a, ok := addr.(*UDPAddr)
 	if !ok {
-		return 0, &OpError{"write", c.fd.net, addr, os.EINVAL}
+		return 0, &OpError{"write", c.fd.net, addr, syscall.EINVAL}
 	}
 	return c.WriteToUDP(b, a)
 }
@@ -262,7 +262,7 @@ func ListenMulticastUDP(net string, ifi *Interface, gaddr *UDPAddr) (*UDPConn, e
 		return nil, UnknownNetworkError(net)
 	}
 	if gaddr == nil || gaddr.IP == nil {
-		return nil, &OpError{"listenmulticastudp", "udp", nil, errMissingAddress}
+		return nil, &OpError{"listenmulticast", net, nil, errMissingAddress}
 	}
 	fd, err := internetSocket(net, gaddr.toAddr(), nil, syscall.SOCK_DGRAM, 0, "listen", sockaddrToUDP)
 	if err != nil {
diff --git a/libgo/go/net/unixsock_plan9.go b/libgo/go/net/unixsock_plan9.go
index 1d9d7578f4f..7b4ae6bd116 100644
--- a/libgo/go/net/unixsock_plan9.go
+++ b/libgo/go/net/unixsock_plan9.go
@@ -7,7 +7,7 @@
 package net
 
 import (
-	"os"
+	"syscall"
 	"time"
 )
 
@@ -19,17 +19,17 @@ type UnixConn bool
 
 // Read implements the Conn Read method.
 func (c *UnixConn) Read(b []byte) (n int, err error) {
-	return 0, os.EPLAN9
+	return 0, syscall.EPLAN9
 }
 
 // Write implements the Conn Write method.
 func (c *UnixConn) Write(b []byte) (n int, err error) {
-	return 0, os.EPLAN9
+	return 0, syscall.EPLAN9
 }
 
 // Close closes the Unix domain connection.
 func (c *UnixConn) Close() error {
-	return os.EPLAN9
+	return syscall.EPLAN9
 }
 
 // LocalAddr returns the local network address, a *UnixAddr.
@@ -47,28 +47,28 @@ func (c *UnixConn) RemoteAddr() Addr {
 
 // SetDeadline implements the Conn SetDeadline method.
 func (c *UnixConn) SetDeadline(t time.Time) error {
-	return os.EPLAN9
+	return syscall.EPLAN9
 }
 
 // SetReadDeadline implements the Conn SetReadDeadline method.
 func (c *UnixConn) SetReadDeadline(t time.Time) error {
-	return os.EPLAN9
+	return syscall.EPLAN9
 }
 
 // SetWriteDeadline implements the Conn SetWriteDeadline method.
 func (c *UnixConn) SetWriteDeadline(t time.Time) error {
-	return os.EPLAN9
+	return syscall.EPLAN9
 }
 
 // ReadFrom implements the PacketConn ReadFrom method.
 func (c *UnixConn) ReadFrom(b []byte) (n int, addr Addr, err error) {
-	err = os.EPLAN9
+	err = syscall.EPLAN9
 	return
 }
 
 // WriteTo implements the PacketConn WriteTo method.
 func (c *UnixConn) WriteTo(b []byte, addr Addr) (n int, err error) {
-	err = os.EPLAN9
+	err = syscall.EPLAN9
 	return
 }
 
@@ -76,7 +76,7 @@ func (c *UnixConn) WriteTo(b []byte, addr Addr) (n int, err error) {
 // which must be "unix" or "unixgram".  If laddr is not nil, it is used
 // as the local address for the connection.
 func DialUnix(net string, laddr, raddr *UnixAddr) (c *UnixConn, err error) {
-	return nil, os.EPLAN9
+	return nil, syscall.EPLAN9
 }
 
 // UnixListener is a Unix domain socket listener.
@@ -87,19 +87,19 @@ type UnixListener bool
 // ListenUnix announces on the Unix domain socket laddr and returns a Unix listener.
 // Net must be "unix" (stream sockets).
 func ListenUnix(net string, laddr *UnixAddr) (l *UnixListener, err error) {
-	return nil, os.EPLAN9
+	return nil, syscall.EPLAN9
 }
 
 // Accept implements the Accept method in the Listener interface;
 // it waits for the next call and returns a generic Conn.
 func (l *UnixListener) Accept() (c Conn, err error) {
-	return nil, os.EPLAN9
+	return nil, syscall.EPLAN9
 }
 
 // Close stops listening on the Unix address.
 // Already accepted connections are not closed.
 func (l *UnixListener) Close() error {
-	return os.EPLAN9
+	return syscall.EPLAN9
 }
 
 // Addr returns the listener's network address.
diff --git a/libgo/go/net/unixsock_posix.go b/libgo/go/net/unixsock_posix.go
index 10b79668511..3a94cf5c5ad 100644
--- a/libgo/go/net/unixsock_posix.go
+++ b/libgo/go/net/unixsock_posix.go
@@ -59,8 +59,8 @@ func unixSocket(net string, laddr, raddr *UnixAddr, mode string) (fd *netFD, err
 		f = sockaddrToUnixpacket
 	}
 
-	fd, oserr := socket(net, syscall.AF_UNIX, sotype, 0, la, ra, f)
-	if oserr != nil {
+	fd, err = socket(net, syscall.AF_UNIX, sotype, 0, la, ra, f)
+	if err != nil {
 		goto Error
 	}
 	return fd, nil
@@ -70,7 +70,7 @@ Error:
 	if mode == "listen" {
 		addr = laddr
 	}
-	return nil, &OpError{Op: mode, Net: net, Addr: addr, Err: oserr}
+	return nil, &OpError{Op: mode, Net: net, Addr: addr, Err: err}
 }
 
 func sockaddrToUnix(sa syscall.Sockaddr) Addr {
@@ -123,7 +123,7 @@ func (c *UnixConn) ok() bool { return c != nil && c.fd != nil }
 // Read implements the Conn Read method.
 func (c *UnixConn) Read(b []byte) (n int, err error) {
 	if !c.ok() {
-		return 0, os.EINVAL
+		return 0, syscall.EINVAL
 	}
 	return c.fd.Read(b)
 }
@@ -131,7 +131,7 @@ func (c *UnixConn) Read(b []byte) (n int, err error) {
 // Write implements the Conn Write method.
 func (c *UnixConn) Write(b []byte) (n int, err error) {
 	if !c.ok() {
-		return 0, os.EINVAL
+		return 0, syscall.EINVAL
 	}
 	return c.fd.Write(b)
 }
@@ -139,7 +139,7 @@ func (c *UnixConn) Write(b []byte) (n int, err error) {
 // Close closes the Unix domain connection.
 func (c *UnixConn) Close() error {
 	if !c.ok() {
-		return os.EINVAL
+		return syscall.EINVAL
 	}
 	err := c.fd.Close()
 	c.fd = nil
@@ -168,7 +168,7 @@ func (c *UnixConn) RemoteAddr() Addr {
 // SetDeadline implements the Conn SetDeadline method.
 func (c *UnixConn) SetDeadline(t time.Time) error {
 	if !c.ok() {
-		return os.EINVAL
+		return syscall.EINVAL
 	}
 	return setDeadline(c.fd, t)
 }
@@ -176,7 +176,7 @@ func (c *UnixConn) SetDeadline(t time.Time) error {
 // SetReadDeadline implements the Conn SetReadDeadline method.
 func (c *UnixConn) SetReadDeadline(t time.Time) error {
 	if !c.ok() {
-		return os.EINVAL
+		return syscall.EINVAL
 	}
 	return setReadDeadline(c.fd, t)
 }
@@ -184,7 +184,7 @@ func (c *UnixConn) SetReadDeadline(t time.Time) error {
 // SetWriteDeadline implements the Conn SetWriteDeadline method.
 func (c *UnixConn) SetWriteDeadline(t time.Time) error {
 	if !c.ok() {
-		return os.EINVAL
+		return syscall.EINVAL
 	}
 	return setWriteDeadline(c.fd, t)
 }
@@ -193,7 +193,7 @@ func (c *UnixConn) SetWriteDeadline(t time.Time) error {
 // receive buffer associated with the connection.
 func (c *UnixConn) SetReadBuffer(bytes int) error {
 	if !c.ok() {
-		return os.EINVAL
+		return syscall.EINVAL
 	}
 	return setReadBuffer(c.fd, bytes)
 }
@@ -202,7 +202,7 @@ func (c *UnixConn) SetReadBuffer(bytes int) error {
 // transmit buffer associated with the connection.
 func (c *UnixConn) SetWriteBuffer(bytes int) error {
 	if !c.ok() {
-		return os.EINVAL
+		return syscall.EINVAL
 	}
 	return setWriteBuffer(c.fd, bytes)
 }
@@ -216,7 +216,7 @@ func (c *UnixConn) SetWriteBuffer(bytes int) error {
 // see SetDeadline and SetReadDeadline.
 func (c *UnixConn) ReadFromUnix(b []byte) (n int, addr *UnixAddr, err error) {
 	if !c.ok() {
-		return 0, nil, os.EINVAL
+		return 0, nil, syscall.EINVAL
 	}
 	n, sa, err := c.fd.ReadFrom(b)
 	switch sa := sa.(type) {
@@ -229,7 +229,7 @@ func (c *UnixConn) ReadFromUnix(b []byte) (n int, addr *UnixAddr, err error) {
 // ReadFrom implements the PacketConn ReadFrom method.
 func (c *UnixConn) ReadFrom(b []byte) (n int, addr Addr, err error) {
 	if !c.ok() {
-		return 0, nil, os.EINVAL
+		return 0, nil, syscall.EINVAL
 	}
 	n, uaddr, err := c.ReadFromUnix(b)
 	return n, uaddr.toAddr(), err
@@ -243,10 +243,10 @@ func (c *UnixConn) ReadFrom(b []byte) (n int, addr Addr, err error) {
 // On packet-oriented connections, write timeouts are rare.
 func (c *UnixConn) WriteToUnix(b []byte, addr *UnixAddr) (n int, err error) {
 	if !c.ok() {
-		return 0, os.EINVAL
+		return 0, syscall.EINVAL
 	}
 	if addr.Net != sotypeToNet(c.fd.sotype) {
-		return 0, os.EAFNOSUPPORT
+		return 0, syscall.EAFNOSUPPORT
 	}
 	sa := &syscall.SockaddrUnix{Name: addr.Name}
 	return c.fd.WriteTo(b, sa)
@@ -255,18 +255,18 @@ func (c *UnixConn) WriteToUnix(b []byte, addr *UnixAddr) (n int, err error) {
 // WriteTo implements the PacketConn WriteTo method.
 func (c *UnixConn) WriteTo(b []byte, addr Addr) (n int, err error) {
 	if !c.ok() {
-		return 0, os.EINVAL
+		return 0, syscall.EINVAL
 	}
 	a, ok := addr.(*UnixAddr)
 	if !ok {
-		return 0, &OpError{"write", c.fd.net, addr, os.EINVAL}
+		return 0, &OpError{"write", c.fd.net, addr, syscall.EINVAL}
 	}
 	return c.WriteToUnix(b, a)
 }
 
 func (c *UnixConn) ReadMsgUnix(b, oob []byte) (n, oobn, flags int, addr *UnixAddr, err error) {
 	if !c.ok() {
-		return 0, 0, 0, nil, os.EINVAL
+		return 0, 0, 0, nil, syscall.EINVAL
 	}
 	n, oobn, flags, sa, err := c.fd.ReadMsg(b, oob)
 	switch sa := sa.(type) {
@@ -278,11 +278,11 @@ func (c *UnixConn) ReadMsgUnix(b, oob []byte) (n, oobn, flags int, addr *UnixAdd
 
 func (c *UnixConn) WriteMsgUnix(b, oob []byte, addr *UnixAddr) (n, oobn int, err error) {
 	if !c.ok() {
-		return 0, 0, os.EINVAL
+		return 0, 0, syscall.EINVAL
 	}
 	if addr != nil {
 		if addr.Net != sotypeToNet(c.fd.sotype) {
-			return 0, 0, os.EAFNOSUPPORT
+			return 0, 0, syscall.EAFNOSUPPORT
 		}
 		sa := &syscall.SockaddrUnix{Name: addr.Name}
 		return c.fd.WriteMsg(b, oob, sa)
@@ -339,7 +339,7 @@ func ListenUnix(net string, laddr *UnixAddr) (*UnixListener, error) {
 // and the remote address.
 func (l *UnixListener) AcceptUnix() (*UnixConn, error) {
 	if l == nil || l.fd == nil {
-		return nil, os.EINVAL
+		return nil, syscall.EINVAL
 	}
 	fd, err := l.fd.accept(sockaddrToUnix)
 	if err != nil {
@@ -363,7 +363,7 @@ func (l *UnixListener) Accept() (c Conn, err error) {
 // Already accepted connections are not closed.
 func (l *UnixListener) Close() error {
 	if l == nil || l.fd == nil {
-		return os.EINVAL
+		return syscall.EINVAL
 	}
 
 	// The operating system doesn't clean up
@@ -391,7 +391,7 @@ func (l *UnixListener) Addr() Addr { return l.fd.laddr }
 // A zero time value disables the deadline.
 func (l *UnixListener) SetDeadline(t time.Time) (err error) {
 	if l == nil || l.fd == nil {
-		return os.EINVAL
+		return syscall.EINVAL
 	}
 	return setDeadline(l.fd, t)
 }
diff --git a/libgo/go/net/url/url.go b/libgo/go/net/url/url.go
index a9ce3b31e24..88ff7ebfef3 100644
--- a/libgo/go/net/url/url.go
+++ b/libgo/go/net/url/url.go
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// Package URL parses URLs and implements query escaping.
+// Package url parses URLs and implements query escaping.
 // See RFC 3986.
 package url
 
@@ -321,19 +321,28 @@ func split(s string, c byte, cutc bool) (string, string) {
 }
 
 // Parse parses rawurl into a URL structure.
-// The string rawurl is assumed not to have a #fragment suffix.
-// (Web browsers strip #fragment before sending the URL to a web server.)
 // The rawurl may be relative or absolute.
 func Parse(rawurl string) (url *URL, err error) {
-	return parse(rawurl, false)
+	// Cut off #frag
+	u, frag := split(rawurl, '#', true)
+	if url, err = parse(u, false); err != nil {
+		return nil, err
+	}
+	if frag == "" {
+		return url, nil
+	}
+	if url.Fragment, err = unescape(frag, encodeFragment); err != nil {
+		return nil, &Error{"parse", rawurl, err}
+	}
+	return url, nil
 }
 
-// ParseRequest parses rawurl into a URL structure.  It assumes that
-// rawurl was received from an HTTP request, so the rawurl is interpreted
+// ParseRequestURI parses rawurl into a URL structure.  It assumes that
+// rawurl was received in an HTTP request, so the rawurl is interpreted
 // only as an absolute URI or an absolute path.
 // The string rawurl is assumed not to have a #fragment suffix.
 // (Web browsers strip #fragment before sending the URL to a web server.)
-func ParseRequest(rawurl string) (url *URL, err error) {
+func ParseRequestURI(rawurl string) (url *URL, err error) {
 	return parse(rawurl, true)
 }
 
@@ -415,22 +424,6 @@ func parseAuthority(authority string) (user *Userinfo, host string, err error) {
 	return
 }
 
-// ParseWithReference is like Parse but allows a trailing #fragment.
-func ParseWithReference(rawurlref string) (url *URL, err error) {
-	// Cut off #frag
-	rawurl, frag := split(rawurlref, '#', true)
-	if url, err = Parse(rawurl); err != nil {
-		return nil, err
-	}
-	if frag == "" {
-		return url, nil
-	}
-	if url.Fragment, err = unescape(frag, encodeFragment); err != nil {
-		return nil, &Error{"parse", rawurlref, err}
-	}
-	return url, nil
-}
-
 // String reassembles the URL into a valid URL string.
 func (u *URL) String() string {
 	// TODO: Rewrite to use bytes.Buffer
@@ -589,15 +582,15 @@ func (u *URL) IsAbs() bool {
 	return u.Scheme != ""
 }
 
-// Parse parses a URL in the context of a base URL.  The URL in ref
+// Parse parses a URL in the context of the receiver.  The provided URL
 // may be relative or absolute.  Parse returns nil, err on parse
 // failure, otherwise its return value is the same as ResolveReference.
-func (base *URL) Parse(ref string) (*URL, error) {
+func (u *URL) Parse(ref string) (*URL, error) {
 	refurl, err := Parse(ref)
 	if err != nil {
 		return nil, err
 	}
-	return base.ResolveReference(refurl), nil
+	return u.ResolveReference(refurl), nil
 }
 
 // ResolveReference resolves a URI reference to an absolute URI from
@@ -606,13 +599,13 @@ func (base *URL) Parse(ref string) (*URL, error) {
 // URL instance, even if the returned URL is identical to either the
 // base or reference. If ref is an absolute URL, then ResolveReference
 // ignores base and returns a copy of ref.
-func (base *URL) ResolveReference(ref *URL) *URL {
+func (u *URL) ResolveReference(ref *URL) *URL {
 	if ref.IsAbs() {
 		url := *ref
 		return &url
 	}
 	// relativeURI = ( net_path | abs_path | rel_path ) [ "?" query ]
-	url := *base
+	url := *u
 	url.RawQuery = ref.RawQuery
 	url.Fragment = ref.Fragment
 	if ref.Opaque != "" {
@@ -632,7 +625,7 @@ func (base *URL) ResolveReference(ref *URL) *URL {
 		url.Path = ref.Path
 	} else {
 		// The "rel_path" case.
-		path := resolvePath(base.Path, ref.Path)
+		path := resolvePath(u.Path, ref.Path)
 		if !strings.HasPrefix(path, "/") {
 			path = "/" + path
 		}
diff --git a/libgo/go/net/url/url_test.go b/libgo/go/net/url/url_test.go
index 9fe5ff886b7..2d911ed505a 100644
--- a/libgo/go/net/url/url_test.go
+++ b/libgo/go/net/url/url_test.go
@@ -188,22 +188,6 @@ var urltests = []URLTest{
 		},
 		"http://user:password@google.com",
 	},
-}
-
-var urlnofragtests = []URLTest{
-	{
-		"http://www.google.com/?q=go+language#foo",
-		&URL{
-			Scheme:   "http",
-			Host:     "www.google.com",
-			Path:     "/",
-			RawQuery: "q=go+language#foo",
-		},
-		"",
-	},
-}
-
-var urlfragtests = []URLTest{
 	{
 		"http://www.google.com/?q=go+language#foo",
 		&URL{
@@ -257,12 +241,6 @@ func DoTest(t *testing.T, parse func(string) (*URL, error), name string, tests [
 
 func TestParse(t *testing.T) {
 	DoTest(t, Parse, "Parse", urltests)
-	DoTest(t, Parse, "Parse", urlnofragtests)
-}
-
-func TestParseWithReference(t *testing.T) {
-	DoTest(t, ParseWithReference, "ParseWithReference", urltests)
-	DoTest(t, ParseWithReference, "ParseWithReference", urlfragtests)
 }
 
 const pathThatLooksSchemeRelative = "//not.a.user@not.a.host/just/a/path"
@@ -281,16 +259,16 @@ var parseRequestUrlTests = []struct {
 	{"../dir/", false},
 }
 
-func TestParseRequest(t *testing.T) {
+func TestParseRequestURI(t *testing.T) {
 	for _, test := range parseRequestUrlTests {
-		_, err := ParseRequest(test.url)
+		_, err := ParseRequestURI(test.url)
 		valid := err == nil
 		if valid != test.expectedValid {
 			t.Errorf("Expected valid=%v for %q; got %v", test.expectedValid, test.url, valid)
 		}
 	}
 
-	url, err := ParseRequest(pathThatLooksSchemeRelative)
+	url, err := ParseRequestURI(pathThatLooksSchemeRelative)
 	if err != nil {
 		t.Fatalf("Unexpected error %v", err)
 	}
@@ -319,9 +297,6 @@ func DoTestString(t *testing.T, parse func(string) (*URL, error), name string, t
 
 func TestURLString(t *testing.T) {
 	DoTestString(t, Parse, "Parse", urltests)
-	DoTestString(t, Parse, "Parse", urlnofragtests)
-	DoTestString(t, ParseWithReference, "ParseWithReference", urltests)
-	DoTestString(t, ParseWithReference, "ParseWithReference", urlfragtests)
 }
 
 type EscapeTest struct {
@@ -538,7 +513,7 @@ var resolveReferenceTests = []struct {
 
 func TestResolveReference(t *testing.T) {
 	mustParse := func(url string) *URL {
-		u, err := ParseWithReference(url)
+		u, err := Parse(url)
 		if err != nil {
 			t.Fatalf("Expected URL to parse: %q, got error: %v", url, err)
 		}
@@ -589,7 +564,7 @@ func TestResolveReference(t *testing.T) {
 
 func TestResolveReferenceOpaque(t *testing.T) {
 	mustParse := func(url string) *URL {
-		u, err := ParseWithReference(url)
+		u, err := Parse(url)
 		if err != nil {
 			t.Fatalf("Expected URL to parse: %q, got error: %v", url, err)
 		}
diff --git a/libgo/go/old/netchan/netchan_test.go b/libgo/go/old/netchan/netchan_test.go
index 53f0f787765..9a7c076d59c 100644
--- a/libgo/go/old/netchan/netchan_test.go
+++ b/libgo/go/old/netchan/netchan_test.go
@@ -291,6 +291,10 @@ func exportLoopback(exp *Exporter, t *testing.T) {
 // This test checks that channel operations can proceed
 // even when other concurrent operations are blocked.
 func TestIndependentSends(t *testing.T) {
+	if testing.Short() {
+		t.Logf("disabled test during -short")
+		return
+	}
 	exp, imp := pair(t)
 
 	exportLoopback(exp, t)
@@ -378,6 +382,10 @@ const flowCount = 100
 
 // test flow control from exporter to importer.
 func TestExportFlowControl(t *testing.T) {
+	if testing.Short() {
+		t.Logf("disabled test during -short")
+		return
+	}
 	exp, imp := pair(t)
 
 	sendDone := make(chan bool, 1)
@@ -394,6 +402,10 @@ func TestExportFlowControl(t *testing.T) {
 
 // test flow control from importer to exporter.
 func TestImportFlowControl(t *testing.T) {
+	if testing.Short() {
+		t.Logf("disabled test during -short")
+		return
+	}
 	exp, imp := pair(t)
 
 	ch := make(chan int)
diff --git a/libgo/go/os/dir_plan9.go b/libgo/go/os/dir_plan9.go
index f2dc15409db..7fa4c7f4449 100644
--- a/libgo/go/os/dir_plan9.go
+++ b/libgo/go/os/dir_plan9.go
@@ -10,6 +10,9 @@ import (
 	"syscall"
 )
 
+var errShortStat = errors.New("short stat message")
+var errBadStat = errors.New("bad stat message format")
+
 func (file *File) readdir(n int) (fi []FileInfo, err error) {
 	// If this file has no dirinfo, create one.
 	if file.dirinfo == nil {
@@ -35,7 +38,7 @@ func (file *File) readdir(n int) (fi []FileInfo, err error) {
 				break
 			}
 			if d.nbuf < syscall.STATFIXLEN {
-				return result, &PathError{"readdir", file.name, Eshortstat}
+				return result, &PathError{"readdir", file.name, errShortStat}
 			}
 		}
 
@@ -43,7 +46,7 @@ func (file *File) readdir(n int) (fi []FileInfo, err error) {
 		m, _ := gbit16(d.buf[d.bufp:])
 		m += 2
 		if m < syscall.STATFIXLEN {
-			return result, &PathError{"readdir", file.name, Eshortstat}
+			return result, &PathError{"readdir", file.name, errShortStat}
 		}
 		dir, e := UnmarshalDir(d.buf[d.bufp : d.bufp+int(m)])
 		if e != nil {
@@ -138,7 +141,7 @@ func UnmarshalDir(b []byte) (d *Dir, err error) {
 	n, b = gbit16(b)
 
 	if int(n) != len(b) {
-		return nil, Ebadstat
+		return nil, errBadStat
 	}
 
 	d = new(Dir)
@@ -155,7 +158,7 @@ func UnmarshalDir(b []byte) (d *Dir, err error) {
 	d.Muid, b = gstring(b)
 
 	if len(b) != 0 {
-		return nil, Ebadstat
+		return nil, errBadStat
 	}
 
 	return d, nil
diff --git a/libgo/go/os/env.go b/libgo/go/os/env.go
index 59350510ccf..eb265f24138 100644
--- a/libgo/go/os/env.go
+++ b/libgo/go/os/env.go
@@ -6,10 +6,7 @@
 
 package os
 
-import (
-	"errors"
-	"syscall"
-)
+import "syscall"
 
 // Expand replaces ${var} or $var in the string based on the mapping function.
 // Invocations of undefined variables are replaced with the empty string.
@@ -77,26 +74,10 @@ func getShellName(s string) (string, int) {
 	return s[:i], i
 }
 
-// ENOENV is the error indicating that an environment variable does not exist.
-var ENOENV = errors.New("no such environment variable")
-
-// Getenverror retrieves the value of the environment variable named by the key.
-// It returns the value and an error, if any.
-func Getenverror(key string) (value string, err error) {
-	if len(key) == 0 {
-		return "", EINVAL
-	}
-	val, found := syscall.Getenv(key)
-	if !found {
-		return "", ENOENV
-	}
-	return val, nil
-}
-
 // Getenv retrieves the value of the environment variable named by the key.
 // It returns the value, which will be empty if the variable is not present.
 func Getenv(key string) string {
-	v, _ := Getenverror(key)
+	v, _ := syscall.Getenv(key)
 	return v
 }
 
diff --git a/libgo/go/os/error.go b/libgo/go/os/error.go
index 135cdae1f9b..e0b83b5c22c 100644
--- a/libgo/go/os/error.go
+++ b/libgo/go/os/error.go
@@ -4,6 +4,18 @@
 
 package os
 
+import (
+	"errors"
+)
+
+// Portable analogs of some common system call errors.
+var (
+	ErrInvalid    = errors.New("invalid argument")
+	ErrPermission = errors.New("permission denied")
+	ErrExist      = errors.New("file already exists")
+	ErrNotExist   = errors.New("file does not exist")
+)
+
 // PathError records an error and the operation and file path that caused it.
 type PathError struct {
 	Op   string
diff --git a/libgo/go/os/error_plan9.go b/libgo/go/os/error_plan9.go
index cc847e07743..159d685e7cd 100644
--- a/libgo/go/os/error_plan9.go
+++ b/libgo/go/os/error_plan9.go
@@ -4,34 +4,38 @@
 
 package os
 
-import (
-	"errors"
-	"syscall"
-)
+// IsExist returns whether the error is known to report that a file already exists.
+func IsExist(err error) bool {
+	if pe, ok := err.(*PathError); ok {
+		err = pe.Err
+	}
+	return contains(err.Error(), " exists")
+}
 
-var (
-	Eshortstat = errors.New("stat buffer too small")
-	Ebadstat   = errors.New("malformed stat buffer")
-	Ebadfd     = errors.New("fd out of range or not open")
-	Ebadarg    = errors.New("bad arg in system call")
-	Enotdir    = errors.New("not a directory")
-	Enonexist  = errors.New("file does not exist")
-	Eexist     = errors.New("file already exists")
-	Eio        = errors.New("i/o error")
-	Eperm      = errors.New("permission denied")
+// IsNotExist returns whether the error is known to report that a file does not exist.
+func IsNotExist(err error) bool {
+	if pe, ok := err.(*PathError); ok {
+		err = pe.Err
+	}
+	return contains(err.Error(), "does not exist")
+}
 
-	EINVAL  = Ebadarg
-	ENOTDIR = Enotdir
-	ENOENT  = Enonexist
-	EEXIST  = Eexist
-	EIO     = Eio
-	EACCES  = Eperm
-	EPERM   = Eperm
-	EISDIR  = syscall.EISDIR
+// IsPermission returns whether the error is known to report that permission is denied.
+func IsPermission(err error) bool {
+	if pe, ok := err.(*PathError); ok {
+		err = pe.Err
+	}
+	return contains(err.Error(), "permission denied")
+}
 
-	EBADF        = errors.New("bad file descriptor")
-	ENAMETOOLONG = errors.New("file name too long")
-	ERANGE       = errors.New("math result not representable")
-	EPIPE        = errors.New("Broken Pipe")
-	EPLAN9       = errors.New("not supported by plan 9")
-)
+// contains is a local version of strings.Contains. It knows len(sep) > 1.
+func contains(s, sep string) bool {
+	n := len(sep)
+	c := sep[0]
+	for i := 0; i+n <= len(s); i++ {
+		if s[i] == c && s[i:i+n] == sep {
+			return true
+		}
+	}
+	return false
+}
diff --git a/libgo/go/os/error_posix.go b/libgo/go/os/error_posix.go
index 57c9b6f2786..74b75d11218 100644
--- a/libgo/go/os/error_posix.go
+++ b/libgo/go/os/error_posix.go
@@ -8,44 +8,29 @@ package os
 
 import "syscall"
 
-// Commonly known Unix errors.
-var (
-	EPERM        error = syscall.EPERM
-	ENOENT       error = syscall.ENOENT
-	ESRCH        error = syscall.ESRCH
-	EINTR        error = syscall.EINTR
-	EIO          error = syscall.EIO
-	E2BIG        error = syscall.E2BIG
-	ENOEXEC      error = syscall.ENOEXEC
-	EBADF        error = syscall.EBADF
-	ECHILD       error = syscall.ECHILD
-	EDEADLK      error = syscall.EDEADLK
-	ENOMEM       error = syscall.ENOMEM
-	EACCES       error = syscall.EACCES
-	EFAULT       error = syscall.EFAULT
-	EBUSY        error = syscall.EBUSY
-	EEXIST       error = syscall.EEXIST
-	EXDEV        error = syscall.EXDEV
-	ENODEV       error = syscall.ENODEV
-	ENOTDIR      error = syscall.ENOTDIR
-	EISDIR       error = syscall.EISDIR
-	EINVAL       error = syscall.EINVAL
-	ENFILE       error = syscall.ENFILE
-	EMFILE       error = syscall.EMFILE
-	ENOTTY       error = syscall.ENOTTY
-	EFBIG        error = syscall.EFBIG
-	ENOSPC       error = syscall.ENOSPC
-	ESPIPE       error = syscall.ESPIPE
-	EROFS        error = syscall.EROFS
-	EMLINK       error = syscall.EMLINK
-	EPIPE        error = syscall.EPIPE
-	EAGAIN       error = syscall.EAGAIN
-	EDOM         error = syscall.EDOM
-	ERANGE       error = syscall.ERANGE
-	EADDRINUSE   error = syscall.EADDRINUSE
-	ECONNREFUSED error = syscall.ECONNREFUSED
-	ENAMETOOLONG error = syscall.ENAMETOOLONG
-	EAFNOSUPPORT error = syscall.EAFNOSUPPORT
-	ETIMEDOUT    error = syscall.ETIMEDOUT
-	ENOTCONN     error = syscall.ENOTCONN
-)
+// IsExist returns whether the error is known to report that a file already exists.
+// It is satisfied by ErrExist as well as some syscall errors.
+func IsExist(err error) bool {
+	if pe, ok := err.(*PathError); ok {
+		err = pe.Err
+	}
+	return err == syscall.EEXIST || err == ErrExist
+}
+
+// IsNotExist returns whether the error is known to report that a file does not exist.
+// It is satisfied by ErrNotExist as well as some syscall errors.
+func IsNotExist(err error) bool {
+	if pe, ok := err.(*PathError); ok {
+		err = pe.Err
+	}
+	return err == syscall.ENOENT || err == ErrNotExist
+}
+
+// IsPermission returns whether the error is known to report that permission is denied.
+// It is satisfied by ErrPermission as well as some syscall errors.
+func IsPermission(err error) bool {
+	if pe, ok := err.(*PathError); ok {
+		err = pe.Err
+	}
+	return err == syscall.EACCES || err == syscall.EPERM || err == ErrPermission
+}
diff --git a/libgo/go/os/exec/exec.go b/libgo/go/os/exec/exec.go
index fe254672169..ebe92a9fba3 100644
--- a/libgo/go/os/exec/exec.go
+++ b/libgo/go/os/exec/exec.go
@@ -79,9 +79,9 @@ type Cmd struct {
 	// Process is the underlying process, once started.
 	Process *os.Process
 
-	// Waitmsg contains information about an exited process,
+	// ProcessState contains information about an exited process,
 	// available after a call to Wait or Run.
-	Waitmsg *os.Waitmsg
+	ProcessState *os.ProcessState
 
 	err             error // last error (from LookPath, stdin, stdout, stderr)
 	finished        bool  // when Wait was called
@@ -266,11 +266,11 @@ func (c *Cmd) Start() error {
 
 // An ExitError reports an unsuccessful exit by a command.
 type ExitError struct {
-	*os.Waitmsg
+	*os.ProcessState
 }
 
 func (e *ExitError) Error() string {
-	return e.Waitmsg.String()
+	return e.ProcessState.String()
 }
 
 // Wait waits for the command to exit.
@@ -291,8 +291,8 @@ func (c *Cmd) Wait() error {
 		return errors.New("exec: Wait was already called")
 	}
 	c.finished = true
-	msg, err := c.Process.Wait(0)
-	c.Waitmsg = msg
+	state, err := c.Process.Wait()
+	c.ProcessState = state
 
 	var copyError error
 	for _ = range c.goroutine {
@@ -307,8 +307,8 @@ func (c *Cmd) Wait() error {
 
 	if err != nil {
 		return err
-	} else if !msg.Exited() || msg.ExitStatus() != 0 {
-		return &ExitError{msg}
+	} else if !state.Success() {
+		return &ExitError{state}
 	}
 
 	return copyError
diff --git a/libgo/go/os/exec/lp_plan9.go b/libgo/go/os/exec/lp_plan9.go
index d88cd0df959..0e229e03ee7 100644
--- a/libgo/go/os/exec/lp_plan9.go
+++ b/libgo/go/os/exec/lp_plan9.go
@@ -8,6 +8,7 @@ import (
 	"errors"
 	"os"
 	"strings"
+	"syscall"
 )
 
 // ErrNotFound is the error resulting if a path search failed to find an executable file.
@@ -21,7 +22,7 @@ func findExecutable(file string) error {
 	if m := d.Mode(); !m.IsDir() && m&0111 != 0 {
 		return nil
 	}
-	return os.EPERM
+	return syscall.EPERM
 }
 
 // LookPath searches for an executable binary named file
diff --git a/libgo/go/os/exec/lp_unix.go b/libgo/go/os/exec/lp_unix.go
index 2d3a919dc6e..21632219972 100644
--- a/libgo/go/os/exec/lp_unix.go
+++ b/libgo/go/os/exec/lp_unix.go
@@ -23,7 +23,7 @@ func findExecutable(file string) error {
 	if m := d.Mode(); !m.IsDir() && m&0111 != 0 {
 		return nil
 	}
-	return os.EPERM
+	return os.ErrPermission
 }
 
 // LookPath searches for an executable binary named file
diff --git a/libgo/go/os/exec/lp_windows.go b/libgo/go/os/exec/lp_windows.go
index b7efcd68b80..d8351d7e6d3 100644
--- a/libgo/go/os/exec/lp_windows.go
+++ b/libgo/go/os/exec/lp_windows.go
@@ -19,7 +19,7 @@ func chkStat(file string) error {
 		return err
 	}
 	if d.IsDir() {
-		return os.EPERM
+		return os.ErrPermission
 	}
 	return nil
 }
@@ -39,7 +39,7 @@ func findExecutable(file string, exts []string) (string, error) {
 			return f, nil
 		}
 	}
-	return ``, os.ENOENT
+	return ``, os.ErrNotExist
 }
 
 // LookPath searches for an executable binary named file
diff --git a/libgo/go/os/exec_plan9.go b/libgo/go/os/exec_plan9.go
index 08f16b86d54..1c9e2b997f8 100644
--- a/libgo/go/os/exec_plan9.go
+++ b/libgo/go/os/exec_plan9.go
@@ -8,6 +8,7 @@ import (
 	"errors"
 	"runtime"
 	"syscall"
+	"time"
 )
 
 // StartProcess starts a new process with the program, arguments and attributes
@@ -20,18 +21,10 @@ func StartProcess(name string, argv []string, attr *ProcAttr) (p *Process, err e
 		Sys: attr.Sys,
 	}
 
-	// Create array of integer (system) fds.
-	intfd := make([]int, len(attr.Files))
-	for i, f := range attr.Files {
-		if f == nil {
-			intfd[i] = -1
-		} else {
-			intfd[i] = f.Fd()
-		}
+	for _, f := range attr.Files {
+		sysattr.Files = append(sysattr.Files, f.Fd())
 	}
 
-	sysattr.Files = intfd
-
 	pid, h, e := syscall.StartProcess(name, argv, sysattr)
 	if e != nil {
 		return nil, &PathError{"fork/exec", name, e}
@@ -72,19 +65,13 @@ func (p *Process) Kill() error {
 	return e
 }
 
-// Waitmsg stores the information about an exited process as reported by Wait.
-type Waitmsg struct {
-	syscall.Waitmsg
-}
-
 // Wait waits for the Process to exit or stop, and then returns a
-// Waitmsg describing its status and an error, if any. The options
-// (WNOHANG etc.) affect the behavior of the Wait call.
-func (p *Process) Wait(options int) (w *Waitmsg, err error) {
+// ProcessState describing its status and an error, if any.
+func (p *Process) Wait() (ps *ProcessState, err error) {
 	var waitmsg syscall.Waitmsg
 
 	if p.Pid == -1 {
-		return nil, EINVAL
+		return nil, ErrInvalid
 	}
 
 	for true {
@@ -100,21 +87,11 @@ func (p *Process) Wait(options int) (w *Waitmsg, err error) {
 		}
 	}
 
-	return &Waitmsg{waitmsg}, nil
-}
-
-// Wait waits for process pid to exit or stop, and then returns a
-// Waitmsg describing its status and an error, if any. The options
-// (WNOHANG etc.) affect the behavior of the Wait call.
-// Wait is equivalent to calling FindProcess and then Wait
-// and Release on the result.
-func Wait(pid int, options int) (w *Waitmsg, err error) {
-	p, e := FindProcess(pid)
-	if e != nil {
-		return nil, e
+	ps = &ProcessState{
+		pid:    waitmsg.Pid,
+		status: &waitmsg,
 	}
-	defer p.Release()
-	return p.Wait(options)
+	return ps, nil
 }
 
 // Release releases any resources associated with the Process.
@@ -131,9 +108,57 @@ func findProcess(pid int) (p *Process, err error) {
 	return newProcess(pid, 0), nil
 }
 
-func (w *Waitmsg) String() string {
-	if w == nil {
+// ProcessState stores information about process as reported by Wait.
+type ProcessState struct {
+	pid    int              // The process's id.
+	status *syscall.Waitmsg // System-dependent status info.
+}
+
+// Pid returns the process id of the exited process.
+func (p *ProcessState) Pid() int {
+	return p.pid
+}
+
+// Exited returns whether the program has exited.
+func (p *ProcessState) Exited() bool {
+	return p.status.Exited()
+}
+
+// Success reports whether the program exited successfully,
+// such as with exit status 0 on Unix.
+func (p *ProcessState) Success() bool {
+	return p.status.ExitStatus() == 0
+}
+
+// Sys returns system-dependent exit information about
+// the process.  Convert it to the appropriate underlying
+// type, such as *syscall.Waitmsg on Plan 9, to access its contents.
+func (p *ProcessState) Sys() interface{} {
+	return p.status
+}
+
+// SysUsage returns system-dependent resource usage information about
+// the exited process.  Convert it to the appropriate underlying
+// type, such as *syscall.Waitmsg on Plan 9, to access its contents.
+func (p *ProcessState) SysUsage() interface{} {
+	return p.status
+}
+
+// UserTime returns the user CPU time of the exited process and its children.
+// It is always reported as 0 on Windows.
+func (p *ProcessState) UserTime() time.Duration {
+	return time.Duration(p.status.Time[0]) * time.Millisecond
+}
+
+// SystemTime returns the system CPU time of the exited process and its children.
+// It is always reported as 0 on Windows.
+func (p *ProcessState) SystemTime() time.Duration {
+	return time.Duration(p.status.Time[1]) * time.Millisecond
+}
+
+func (p *ProcessState) String() string {
+	if p == nil {
 		return "<nil>"
 	}
-	return "exit status: " + w.Msg
+	return "exit status: " + p.status.Msg
 }
diff --git a/libgo/go/os/exec_posix.go b/libgo/go/os/exec_posix.go
index 33a689eb045..4a75cb67fb5 100644
--- a/libgo/go/os/exec_posix.go
+++ b/libgo/go/os/exec_posix.go
@@ -42,32 +42,41 @@ func (p *Process) Kill() error {
 	return p.Signal(Kill)
 }
 
-// TODO(rsc): Should os implement its own syscall.WaitStatus
-// wrapper with the methods, or is exposing the underlying one enough?
-//
-// TODO(rsc): Certainly need to have Rusage struct,
-// since syscall one might have different field types across
-// different OS.
-
-// Waitmsg stores the information about an exited process as reported by Wait.
-type Waitmsg struct {
-	Pid                int             // The process's id.
-	syscall.WaitStatus                 // System-dependent status info.
-	Rusage             *syscall.Rusage // System-dependent resource usage info.
+// ProcessState stores information about process as reported by Wait.
+type ProcessState struct {
+	pid    int                // The process's id.
+	status syscall.WaitStatus // System-dependent status info.
+	rusage *syscall.Rusage
 }
 
-// Wait waits for process pid to exit or stop, and then returns a
-// Waitmsg describing its status and an error, if any. The options
-// (WNOHANG etc.) affect the behavior of the Wait call.
-// Wait is equivalent to calling FindProcess and then Wait
-// and Release on the result.
-func Wait(pid int, options int) (w *Waitmsg, err error) {
-	p, e := FindProcess(pid)
-	if e != nil {
-		return nil, e
-	}
-	defer p.Release()
-	return p.Wait(options)
+// Pid returns the process id of the exited process.
+func (p *ProcessState) Pid() int {
+	return p.pid
+}
+
+// Exited returns whether the program has exited.
+func (p *ProcessState) Exited() bool {
+	return p.status.Exited()
+}
+
+// Success reports whether the program exited successfully,
+// such as with exit status 0 on Unix.
+func (p *ProcessState) Success() bool {
+	return p.status.ExitStatus() == 0
+}
+
+// Sys returns system-dependent exit information about
+// the process.  Convert it to the appropriate underlying
+// type, such as syscall.WaitStatus on Unix, to access its contents.
+func (p *ProcessState) Sys() interface{} {
+	return p.status
+}
+
+// SysUsage returns system-dependent resource usage information about
+// the exited process.  Convert it to the appropriate underlying
+// type, such as *syscall.Rusage on Unix, to access its contents.
+func (p *ProcessState) SysUsage() interface{} {
+	return p.rusage
 }
 
 // Convert i to decimal string.
@@ -97,26 +106,26 @@ func itod(i int) string {
 	return string(b[bp:])
 }
 
-func (w *Waitmsg) String() string {
-	if w == nil {
+func (p *ProcessState) String() string {
+	if p == nil {
 		return "<nil>"
 	}
-	// TODO(austin) Use signal names when possible?
+	status := p.Sys().(syscall.WaitStatus)
 	res := ""
 	switch {
-	case w.Exited():
-		res = "exit status " + itod(w.ExitStatus())
-	case w.Signaled():
-		res = "signal " + itod(int(w.Signal()))
-	case w.Stopped():
-		res = "stop signal " + itod(int(w.StopSignal()))
-		if w.StopSignal() == syscall.SIGTRAP && w.TrapCause() != 0 {
-			res += " (trap " + itod(w.TrapCause()) + ")"
+	case status.Exited():
+		res = "exit status " + itod(status.ExitStatus())
+	case status.Signaled():
+		res = "signal " + itod(int(status.Signal()))
+	case status.Stopped():
+		res = "stop signal " + itod(int(status.StopSignal()))
+		if status.StopSignal() == syscall.SIGTRAP && status.TrapCause() != 0 {
+			res += " (trap " + itod(status.TrapCause()) + ")"
 		}
-	case w.Continued():
+	case status.Continued():
 		res = "continued"
 	}
-	if w.CoreDump() {
+	if status.CoreDump() {
 		res += " (core dumped)"
 	}
 	return res
diff --git a/libgo/go/os/exec_unix.go b/libgo/go/os/exec_unix.go
index 7fe7c2fe8cd..8d000e9ef15 100644
--- a/libgo/go/os/exec_unix.go
+++ b/libgo/go/os/exec_unix.go
@@ -10,46 +10,30 @@ import (
 	"errors"
 	"runtime"
 	"syscall"
+	"time"
 )
 
-// Options for Wait.
-const (
-	WNOHANG   = syscall.WNOHANG   // Don't wait if no process has exited.
-	WSTOPPED  = syscall.WSTOPPED  // If set, status of stopped subprocesses is also reported.
-	WUNTRACED = syscall.WUNTRACED // Usually an alias for WSTOPPED.
-	WRUSAGE   = 1 << 20           // Record resource usage.
-)
-
-// WRUSAGE must not be too high a bit, to avoid clashing with Linux's
-// WCLONE, WALL, and WNOTHREAD flags, which sit in the top few bits of
-// the options
-
 // Wait waits for the Process to exit or stop, and then returns a
-// Waitmsg describing its status and an error, if any. The options
-// (WNOHANG etc.) affect the behavior of the Wait call.
-func (p *Process) Wait(options int) (w *Waitmsg, err error) {
+// ProcessState describing its status and an error, if any.
+func (p *Process) Wait() (ps *ProcessState, err error) {
 	if p.Pid == -1 {
-		return nil, EINVAL
+		return nil, syscall.EINVAL
 	}
 	var status syscall.WaitStatus
-	var rusage *syscall.Rusage
-	if options&WRUSAGE != 0 {
-		rusage = new(syscall.Rusage)
-		options ^= WRUSAGE
-	}
-	pid1, e := syscall.Wait4(p.Pid, &status, options, rusage)
+	var rusage syscall.Rusage
+	pid1, e := syscall.Wait4(p.Pid, &status, 0, &rusage)
 	if e != nil {
 		return nil, NewSyscallError("wait", e)
 	}
-	// With WNOHANG pid is 0 if child has not exited.
-	if pid1 != 0 && options&WSTOPPED == 0 {
+	if pid1 != 0 {
 		p.done = true
 	}
-	w = new(Waitmsg)
-	w.Pid = pid1
-	w.WaitStatus = status
-	w.Rusage = rusage
-	return w, nil
+	ps = &ProcessState{
+		pid:    pid1,
+		status: status,
+		rusage: &rusage,
+	}
+	return ps, nil
 }
 
 // Signal sends a signal to the Process.
@@ -80,3 +64,13 @@ func findProcess(pid int) (p *Process, err error) {
 	// NOOP for unix.
 	return newProcess(pid, 0), nil
 }
+
+// UserTime returns the user CPU time of the exited process and its children.
+func (p *ProcessState) UserTime() time.Duration {
+	return time.Duration(p.rusage.Utime.Nano()) * time.Nanosecond
+}
+
+// SystemTime returns the system CPU time of the exited process and its children.
+func (p *ProcessState) SystemTime() time.Duration {
+	return time.Duration(p.rusage.Stime.Nano()) * time.Nanosecond
+}
diff --git a/libgo/go/os/exec_windows.go b/libgo/go/os/exec_windows.go
index f357a3034b1..dab0dc97571 100644
--- a/libgo/go/os/exec_windows.go
+++ b/libgo/go/os/exec_windows.go
@@ -8,12 +8,13 @@ import (
 	"errors"
 	"runtime"
 	"syscall"
+	"time"
 	"unsafe"
 )
 
 // Wait waits for the Process to exit or stop, and then returns a
-// Waitmsg describing its status and an error, if any.
-func (p *Process) Wait(options int) (w *Waitmsg, err error) {
+// ProcessState describing its status and an error, if any.
+func (p *Process) Wait() (ps *ProcessState, err error) {
 	s, e := syscall.WaitForSingleObject(syscall.Handle(p.handle), syscall.INFINITE)
 	switch s {
 	case syscall.WAIT_OBJECT_0:
@@ -29,7 +30,7 @@ func (p *Process) Wait(options int) (w *Waitmsg, err error) {
 		return nil, NewSyscallError("GetExitCodeProcess", e)
 	}
 	p.done = true
-	return &Waitmsg{p.Pid, syscall.WaitStatus{Status: s, ExitCode: ec}, new(syscall.Rusage)}, nil
+	return &ProcessState{p.Pid, syscall.WaitStatus{Status: s, ExitCode: ec}, new(syscall.Rusage)}, nil
 }
 
 // Signal sends a signal to the Process.
@@ -48,7 +49,7 @@ func (p *Process) Signal(sig Signal) error {
 // Release releases any resources associated with the Process.
 func (p *Process) Release() error {
 	if p.handle == uintptr(syscall.InvalidHandle) {
-		return EINVAL
+		return syscall.EINVAL
 	}
 	e := syscall.CloseHandle(syscall.Handle(p.handle))
 	if e != nil {
@@ -83,3 +84,15 @@ func init() {
 		Args[i] = string(syscall.UTF16ToString((*v)[:]))
 	}
 }
+
+// UserTime returns the user CPU time of the exited process and its children.
+// For now, it is always reported as 0 on Windows.
+func (p *ProcessState) UserTime() time.Duration {
+	return 0
+}
+
+// SystemTime returns the system CPU time of the exited process and its children.
+// For now, it is always reported as 0 on Windows.
+func (p *ProcessState) SystemTime() time.Duration {
+	return 0
+}
diff --git a/libgo/go/os/file.go b/libgo/go/os/file.go
index 85f151e2840..1c3d0172d34 100644
--- a/libgo/go/os/file.go
+++ b/libgo/go/os/file.go
@@ -7,11 +7,33 @@
 // Go-like; failing calls return values of type error rather than error numbers.
 // Often, more information is available within the error. For example,
 // if a call that takes a file name fails, such as Open or Stat, the error
-// will include failing file name when printed and will be of type *PathError,
-// which may be unpacked for more information.
+// will include the failing file name when printed and will be of type
+// *PathError, which may be unpacked for more information.
 // 
 // The os interface is intended to be uniform across all operating systems.
 // Features not generally available appear in the system-specific package syscall.
+//
+// Here is a simple example, opening a file and reading some of it.
+//
+//	file, err := os.Open("file.go") // For read access.
+//	if err != nil {
+//		log.Fatal(err)
+//	}
+//
+// If the open fails, the error string will be self-explanatory, like
+//
+//	open file.go: no such file or directory
+//
+// The file's data can then be read into a slice of bytes. Read and
+// Write take their byte counts from the length of the artument slice.
+//
+//	data := make([]byte, 100)
+//	count, err := file.Read(data)
+//	if err != nil {
+//		log.Fatal(err)
+//	}
+//	fmt.Printf("read %d bytes: %q\n", count, data[:count])
+//
 package os
 
 import (
@@ -50,12 +72,25 @@ const (
 	SEEK_END int = 2 // seek relative to the end
 )
 
+// LinkError records an error during a link or symlink or rename
+// system call and the paths that caused it.
+type LinkError struct {
+	Op  string
+	Old string
+	New string
+	Err error
+}
+
+func (e *LinkError) Error() string {
+	return e.Op + " " + e.Old + " " + e.New + ": " + e.Err.Error()
+}
+
 // Read reads up to len(b) bytes from the File.
 // It returns the number of bytes read and an error, if any.
 // EOF is signaled by a zero count with err set to io.EOF.
 func (f *File) Read(b []byte) (n int, err error) {
 	if f == nil {
-		return 0, EINVAL
+		return 0, ErrInvalid
 	}
 	n, e := f.read(b)
 	if n < 0 {
@@ -76,7 +111,7 @@ func (f *File) Read(b []byte) (n int, err error) {
 // At end of file, that error is io.EOF.
 func (f *File) ReadAt(b []byte, off int64) (n int, err error) {
 	if f == nil {
-		return 0, EINVAL
+		return 0, ErrInvalid
 	}
 	for len(b) > 0 {
 		m, e := f.pread(b, off)
@@ -99,7 +134,7 @@ func (f *File) ReadAt(b []byte, off int64) (n int, err error) {
 // Write returns a non-nil error when n != len(b).
 func (f *File) Write(b []byte) (n int, err error) {
 	if f == nil {
-		return 0, EINVAL
+		return 0, ErrInvalid
 	}
 	n, e := f.write(b)
 	if n < 0 {
@@ -119,7 +154,7 @@ func (f *File) Write(b []byte) (n int, err error) {
 // WriteAt returns a non-nil error when n != len(b).
 func (f *File) WriteAt(b []byte, off int64) (n int, err error) {
 	if f == nil {
-		return 0, EINVAL
+		return 0, ErrInvalid
 	}
 	for len(b) > 0 {
 		m, e := f.pwrite(b, off)
@@ -153,7 +188,7 @@ func (f *File) Seek(offset int64, whence int) (ret int64, err error) {
 // an array of bytes.
 func (f *File) WriteString(s string) (ret int, err error) {
 	if f == nil {
-		return 0, EINVAL
+		return 0, ErrInvalid
 	}
 	return f.Write([]byte(s))
 }
diff --git a/libgo/go/os/file_plan9.go b/libgo/go/os/file_plan9.go
index fed2b809175..cb0e9ef9289 100644
--- a/libgo/go/os/file_plan9.go
+++ b/libgo/go/os/file_plan9.go
@@ -5,11 +5,14 @@
 package os
 
 import (
+	"errors"
 	"runtime"
 	"syscall"
 	"time"
 )
 
+var ErrPlan9 = errors.New("unimplemented on Plan 9")
+
 // File represents an open file descriptor.
 type File struct {
 	*file
@@ -26,19 +29,20 @@ type file struct {
 }
 
 // Fd returns the integer Unix file descriptor referencing the open file.
-func (file *File) Fd() int {
-	if file == nil {
-		return -1
+func (f *File) Fd() uintptr {
+	if f == nil {
+		return ^(uintptr(0))
 	}
-	return file.fd
+	return uintptr(f.fd)
 }
 
 // NewFile returns a new File with the given file descriptor and name.
-func NewFile(fd int, name string) *File {
-	if fd < 0 {
+func NewFile(fd uintptr, name string) *File {
+	fdi := int(fd)
+	if fdi < 0 {
 		return nil
 	}
-	f := &File{&file{fd: fd, name: name}}
+	f := &File{&file{fd: fdi, name: name}}
 	runtime.SetFinalizer(f.file, (*file).close)
 	return f
 }
@@ -128,7 +132,7 @@ func OpenFile(name string, flag int, perm FileMode) (file *File, err error) {
 		}
 	}
 
-	return NewFile(fd, name), nil
+	return NewFile(uintptr(fd), name), nil
 }
 
 // Close closes the File, rendering it unusable for I/O.
@@ -139,7 +143,7 @@ func (file *File) Close() error {
 
 func (file *file) close() error {
 	if file == nil || file.fd < 0 {
-		return Ebadfd
+		return ErrInvalid
 	}
 	var err error
 	syscall.ForkLock.RLock()
@@ -202,7 +206,7 @@ func (f *File) Chmod(mode FileMode) error {
 // of recently written data to disk.
 func (f *File) Sync() (err error) {
 	if f == nil {
-		return EINVAL
+		return ErrInvalid
 	}
 
 	var d Dir
@@ -272,7 +276,6 @@ func Remove(name string) error {
 }
 
 // Rename renames a file.
-// If there is an error, it will be of type *PathError.
 func Rename(oldname, newname string) error {
 	var d Dir
 	d.Null()
@@ -330,34 +333,37 @@ func Pipe() (r *File, w *File, err error) {
 	}
 	syscall.ForkLock.RUnlock()
 
-	return NewFile(p[0], "|0"), NewFile(p[1], "|1"), nil
+	return NewFile(uintptr(p[0]), "|0"), NewFile(uintptr(p[1]), "|1"), nil
 }
 
 // not supported on Plan 9
 
 // Link creates a hard link.
+// If there is an error, it will be of type *LinkError.
 func Link(oldname, newname string) error {
-	return EPLAN9
+	return &LinkError{"link", oldname, newname, ErrPlan9}
 }
 
+// Symlink creates newname as a symbolic link to oldname.
+// If there is an error, it will be of type *LinkError.
 func Symlink(oldname, newname string) error {
-	return EPLAN9
+	return &LinkError{"symlink", oldname, newname, ErrPlan9}
 }
 
 func Readlink(name string) (string, error) {
-	return "", EPLAN9
+	return "", ErrPlan9
 }
 
 func Chown(name string, uid, gid int) error {
-	return EPLAN9
+	return ErrPlan9
 }
 
 func Lchown(name string, uid, gid int) error {
-	return EPLAN9
+	return ErrPlan9
 }
 
 func (f *File) Chown(uid, gid int) error {
-	return EPLAN9
+	return ErrPlan9
 }
 
 // TempDir returns the default directory to use for temporary files.
diff --git a/libgo/go/os/file_posix.go b/libgo/go/os/file_posix.go
index 8d3a00b6c5a..073bd56a471 100644
--- a/libgo/go/os/file_posix.go
+++ b/libgo/go/os/file_posix.go
@@ -24,20 +24,8 @@ func epipecheck(file *File, e error) {
 	}
 }
 
-// LinkError records an error during a link or symlink or rename
-// system call and the paths that caused it.
-type LinkError struct {
-	Op  string
-	Old string
-	New string
-	Err error
-}
-
-func (e *LinkError) Error() string {
-	return e.Op + " " + e.Old + " " + e.New + ": " + e.Err.Error()
-}
-
 // Link creates newname as a hard link to the oldname file.
+// If there is an error, it will be of type *LinkError.
 func Link(oldname, newname string) error {
 	e := syscall.Link(oldname, newname)
 	if e != nil {
@@ -47,6 +35,7 @@ func Link(oldname, newname string) error {
 }
 
 // Symlink creates newname as a symbolic link to oldname.
+// If there is an error, it will be of type *LinkError.
 func Symlink(oldname, newname string) error {
 	e := syscall.Symlink(oldname, newname)
 	if e != nil {
@@ -160,7 +149,7 @@ func (f *File) Truncate(size int64) error {
 // of recently written data to disk.
 func (f *File) Sync() (err error) {
 	if f == nil {
-		return EINVAL
+		return syscall.EINVAL
 	}
 	if e := syscall.Fsync(f.fd); e != nil {
 		return NewSyscallError("fsync", e)
diff --git a/libgo/go/os/file_unix.go b/libgo/go/os/file_unix.go
index 3d659efe061..a69680cb8c9 100644
--- a/libgo/go/os/file_unix.go
+++ b/libgo/go/os/file_unix.go
@@ -89,7 +89,7 @@ func (f *File) Close() error {
 
 func (file *file) close() error {
 	if file == nil || file.fd < 0 {
-		return EINVAL
+		return syscall.EINVAL
 	}
 	var err error
 	if e := syscall.Close(file.fd); e != nil {
diff --git a/libgo/go/os/getwd.go b/libgo/go/os/getwd.go
index 56836434dbe..81d8fed926e 100644
--- a/libgo/go/os/getwd.go
+++ b/libgo/go/os/getwd.go
@@ -52,7 +52,7 @@ func Getwd() (pwd string, err error) {
 	pwd = ""
 	for parent := ".."; ; parent = "../" + parent {
 		if len(parent) >= 1024 { // Sanity check
-			return "", ENAMETOOLONG
+			return "", syscall.ENAMETOOLONG
 		}
 		fd, err := Open(parent)
 		if err != nil {
@@ -74,7 +74,7 @@ func Getwd() (pwd string, err error) {
 			}
 		}
 		fd.Close()
-		return "", ENOENT
+		return "", ErrNotExist
 
 	Found:
 		pd, err := fd.Stat()
diff --git a/libgo/go/os/os_test.go b/libgo/go/os/os_test.go
index 27436dadcda..cff35fcef75 100644
--- a/libgo/go/os/os_test.go
+++ b/libgo/go/os/os_test.go
@@ -13,6 +13,7 @@ import (
 	"path/filepath"
 	"runtime"
 	"strings"
+	"syscall"
 	"testing"
 	"time"
 )
@@ -538,7 +539,7 @@ func exec(t *testing.T, dir, cmd string, args []string, expect string) {
 		t.Errorf("exec %q returned %q wanted %q",
 			strings.Join(append([]string{cmd}, args...), " "), output, expect)
 	}
-	p.Wait(0)
+	p.Wait()
 }
 
 func TestStartProcess(t *testing.T) {
@@ -767,7 +768,7 @@ func TestSeek(t *testing.T) {
 	for i, tt := range tests {
 		off, err := f.Seek(tt.in, tt.whence)
 		if off != tt.out || err != nil {
-			if e, ok := err.(*PathError); ok && e.Err == EINVAL && tt.out > 1<<32 {
+			if e, ok := err.(*PathError); ok && e.Err == syscall.EINVAL && tt.out > 1<<32 {
 				// Reiserfs rejects the big seeks.
 				// http://code.google.com/p/go/issues/detail?id=91
 				break
@@ -787,17 +788,17 @@ var openErrorTests = []openErrorTest{
 	{
 		sfdir + "/no-such-file",
 		O_RDONLY,
-		ENOENT,
+		syscall.ENOENT,
 	},
 	{
 		sfdir,
 		O_WRONLY,
-		EISDIR,
+		syscall.EISDIR,
 	},
 	{
 		sfdir + "/" + sfname + "/no-such-file",
 		O_WRONLY,
-		ENOTDIR,
+		syscall.ENOTDIR,
 	},
 }
 
@@ -850,7 +851,7 @@ func run(t *testing.T, cmd []string) string {
 
 	var b bytes.Buffer
 	io.Copy(&b, r)
-	_, err = p.Wait(0)
+	_, err = p.Wait()
 	if err != nil {
 		t.Fatalf("run hostname Wait: %v", err)
 	}
@@ -983,32 +984,31 @@ func TestAppend(t *testing.T) {
 }
 
 func TestStatDirWithTrailingSlash(t *testing.T) {
-	// Create new dir, in _test so it will get
-	// cleaned up by make if not by us.
-	path := "_test/_TestStatDirWithSlash_"
-	err := MkdirAll(path, 0777)
+	// Create new temporary directory and arrange to clean it up.
+	path, err := ioutil.TempDir("", "/_TestStatDirWithSlash_")
 	if err != nil {
-		t.Fatalf("MkdirAll %q: %s", path, err)
+		t.Fatalf("TempDir: %s", err)
 	}
 	defer RemoveAll(path)
 
 	// Stat of path should succeed.
 	_, err = Stat(path)
 	if err != nil {
-		t.Fatal("stat failed:", err)
+		t.Fatalf("stat %s failed: %s", path, err)
 	}
 
 	// Stat of path+"/" should succeed too.
-	_, err = Stat(path + "/")
+	path += "/"
+	_, err = Stat(path)
 	if err != nil {
-		t.Fatal("stat failed:", err)
+		t.Fatalf("stat %s failed: %s", path, err)
 	}
 }
 
-func TestNilWaitmsgString(t *testing.T) {
-	var w *Waitmsg
-	s := w.String()
+func TestNilProcessStateString(t *testing.T) {
+	var ps *ProcessState
+	s := ps.String()
 	if s != "<nil>" {
-		t.Errorf("(*Waitmsg)(nil).String() = %q, want %q", s, "<nil>")
+		t.Errorf("(*ProcessState)(nil).String() = %q, want %q", s, "<nil>")
 	}
 }
diff --git a/libgo/go/os/path.go b/libgo/go/os/path.go
index e962f3e397b..02a77ec8051 100644
--- a/libgo/go/os/path.go
+++ b/libgo/go/os/path.go
@@ -4,7 +4,10 @@
 
 package os
 
-import "io"
+import (
+	"io"
+	"syscall"
+)
 
 // MkdirAll creates a directory named path,
 // along with any necessary parents, and returns nil,
@@ -20,7 +23,7 @@ func MkdirAll(path string, perm FileMode) error {
 		if dir.IsDir() {
 			return nil
 		}
-		return &PathError{"mkdir", path, ENOTDIR}
+		return &PathError{"mkdir", path, syscall.ENOTDIR}
 	}
 
 	// Doesn't already exist; make sure parent does.
@@ -70,7 +73,7 @@ func RemoveAll(path string) error {
 	// Otherwise, is this a directory we need to recurse into?
 	dir, serr := Lstat(path)
 	if serr != nil {
-		if serr, ok := serr.(*PathError); ok && (serr.Err == ENOENT || serr.Err == ENOTDIR) {
+		if serr, ok := serr.(*PathError); ok && (IsNotExist(serr.Err) || serr.Err == syscall.ENOTDIR) {
 			return nil
 		}
 		return serr
diff --git a/libgo/go/os/path_test.go b/libgo/go/os/path_test.go
index 18634ba410e..c1e3fb35436 100644
--- a/libgo/go/os/path_test.go
+++ b/libgo/go/os/path_test.go
@@ -8,18 +8,18 @@ import (
 	. "os"
 	"path/filepath"
 	"runtime"
+	"syscall"
 	"testing"
 )
 
 func TestMkdirAll(t *testing.T) {
-	// Create new dir, in _test so it will get
-	// cleaned up by make if not by us.
-	path := "_test/_TestMkdirAll_/dir/./dir2"
+	tmpDir := TempDir()
+	path := tmpDir + "/_TestMkdirAll_/dir/./dir2"
 	err := MkdirAll(path, 0777)
 	if err != nil {
 		t.Fatalf("MkdirAll %q: %s", path, err)
 	}
-	defer RemoveAll("_test/_TestMkdirAll_")
+	defer RemoveAll(tmpDir + "/_TestMkdirAll_")
 
 	// Already exists, should succeed.
 	err = MkdirAll(path, 0777)
@@ -63,7 +63,7 @@ func TestMkdirAll(t *testing.T) {
 	}
 
 	if runtime.GOOS == "windows" {
-		path := `_test\_TestMkdirAll_\dir\.\dir2\`
+		path := tmpDir + `\_TestMkdirAll_\dir\.\dir2\`
 		err := MkdirAll(path, 0777)
 		if err != nil {
 			t.Fatalf("MkdirAll %q: %s", path, err)
@@ -72,8 +72,9 @@ func TestMkdirAll(t *testing.T) {
 }
 
 func TestRemoveAll(t *testing.T) {
+	tmpDir := TempDir()
 	// Work directory.
-	path := "_test/_TestRemoveAll_"
+	path := tmpDir + "/_TestRemoveAll_"
 	fpath := path + "/file"
 	dpath := path + "/dir"
 
@@ -170,19 +171,22 @@ func TestMkdirAllWithSymlink(t *testing.T) {
 		return
 	}
 
-	err := Mkdir("_test/dir", 0755)
+	tmpDir := TempDir()
+	dir := tmpDir + "/dir"
+	err := Mkdir(dir, 0755)
 	if err != nil {
-		t.Fatal(`Mkdir "_test/dir":`, err)
+		t.Fatalf("Mkdir %s: %s", dir, err)
 	}
-	defer RemoveAll("_test/dir")
+	defer RemoveAll(dir)
 
-	err = Symlink("dir", "_test/link")
+	link := tmpDir + "/link"
+	err = Symlink("dir", link)
 	if err != nil {
-		t.Fatal(`Symlink "dir", "_test/link":`, err)
+		t.Fatalf("Symlink %s: %s", link, err)
 	}
-	defer RemoveAll("_test/link")
+	defer RemoveAll(link)
 
-	path := "_test/link/foo"
+	path := link + "/foo"
 	err = MkdirAll(path, 0755)
 	if err != nil {
 		t.Errorf("MkdirAll %q: %s", path, err)
@@ -198,7 +202,7 @@ func TestMkdirAllAtSlash(t *testing.T) {
 	if err != nil {
 		pathErr, ok := err.(*PathError)
 		// common for users not to be able to write to /
-		if ok && pathErr.Err == EACCES {
+		if ok && pathErr.Err == syscall.EACCES {
 			return
 		}
 		t.Fatalf(`MkdirAll "/_go_os_test/dir": %v`, err)
diff --git a/libgo/go/os/signal/signal_stub.go b/libgo/go/os/signal/signal_stub.go
new file mode 100644
index 00000000000..fc227cf4c2d
--- /dev/null
+++ b/libgo/go/os/signal/signal_stub.go
@@ -0,0 +1,11 @@
+// Copyright 2012 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.
+
+// +build plan9
+
+package signal
+
+import "os"
+
+func enableSignal(sig os.Signal) {}
diff --git a/libgo/go/os/stat_plan9.go b/libgo/go/os/stat_plan9.go
index 00622581f4f..a7990a359ec 100644
--- a/libgo/go/os/stat_plan9.go
+++ b/libgo/go/os/stat_plan9.go
@@ -62,7 +62,7 @@ func dirstat(arg interface{}) (d *Dir, err error) {
 			return nil, &PathError{"stat", name, err}
 		}
 		if n < syscall.STATFIXLEN {
-			return nil, &PathError{"stat", name, Eshortstat}
+			return nil, &PathError{"stat", name, errShortStat}
 		}
 
 		// Pull the real size out of the stat message.
@@ -79,7 +79,7 @@ func dirstat(arg interface{}) (d *Dir, err error) {
 			return
 		}
 	}
-	return nil, &PathError{"stat", name, Ebadstat}
+	return nil, &PathError{"stat", name, errBadStat}
 }
 
 // Stat returns a FileInfo structure describing the named file.
diff --git a/libgo/go/path/example_test.go b/libgo/go/path/example_test.go
index f0ac1301408..ca18b32305e 100644
--- a/libgo/go/path/example_test.go
+++ b/libgo/go/path/example_test.go
@@ -11,17 +11,11 @@ import (
 	"path"
 )
 
-// b
 func ExampleBase() {
 	fmt.Println(path.Base("/a/b"))
+	// Output: b
 }
 
-// Clean("a/c") = "a/c"
-// Clean("a//c") = "a/c"
-// Clean("a/c/.") = "a/c"
-// Clean("a/c/b/..") = "a/c"
-// Clean("/../a/c") = "/a/c"
-// Clean("/../a/b/../././/c") = "/a/c"
 func ExampleClean() {
 	paths := []string{
 		"a/c",
@@ -35,31 +29,39 @@ func ExampleClean() {
 	for _, p := range paths {
 		fmt.Printf("Clean(%q) = %q\n", p, path.Clean(p))
 	}
+
+	// Output:
+	// Clean("a/c") = "a/c"
+	// Clean("a//c") = "a/c"
+	// Clean("a/c/.") = "a/c"
+	// Clean("a/c/b/..") = "a/c"
+	// Clean("/../a/c") = "/a/c"
+	// Clean("/../a/b/../././/c") = "/a/c"
 }
 
-// /a/b
 func ExampleDir() {
 	fmt.Println(path.Dir("/a/b/c"))
+	// Output: /a/b
 }
 
-// .css
 func ExampleExt() {
 	fmt.Println(path.Ext("/a/b/c/bar.css"))
+	// Output: .css
 }
 
-// true
 func ExampleIsAbs() {
 	fmt.Println(path.IsAbs("/dev/null"))
+	// Output: true
 }
 
-// a/b/c
 func ExampleJoin() {
 	fmt.Println(path.Join("a", "b", "c"))
+	// Output: a/b/c
 }
 
-// static/ myfile.css
 func ExampleSplit() {
 	fmt.Println(path.Split("static/myfile.css"))
+	// Output: static/ myfile.css
 }
 
 */
diff --git a/libgo/go/path/filepath/match.go b/libgo/go/path/filepath/match.go
index c3678f541d4..38d264fb97a 100644
--- a/libgo/go/path/filepath/match.go
+++ b/libgo/go/path/filepath/match.go
@@ -12,6 +12,7 @@ import (
 	"unicode/utf8"
 )
 
+// ErrBadPattern indicates a globbing pattern was malformed.
 var ErrBadPattern = errors.New("syntax error in pattern")
 
 // Match returns true if name matches the shell file name pattern.
@@ -33,7 +34,8 @@ var ErrBadPattern = errors.New("syntax error in pattern")
 //		lo '-' hi   matches character c for lo <= c <= hi
 //
 // Match requires pattern to match all of name, not just a substring.
-// The only possible error return occurs when the pattern is malformed.
+// The only possible returned error is ErrBadPattern, when pattern
+// is malformed.
 //
 func Match(pattern, name string) (matched bool, err error) {
 Pattern:
@@ -211,7 +213,6 @@ func getEsc(chunk string) (r rune, nchunk string, err error) {
 // if there is no matching file. The syntax of patterns is the same
 // as in Match. The pattern may describe hierarchical names such as
 // /usr/*/bin/ed (assuming the Separator is '/').
-// The only possible error return occurs when the pattern is malformed.
 //
 func Glob(pattern string) (matches []string, err error) {
 	if !hasMeta(pattern) {
@@ -253,7 +254,6 @@ func Glob(pattern string) (matches []string, err error) {
 // and appends them to matches. If the directory cannot be
 // opened, it returns the existing matches. New matches are
 // added in lexicographical order.
-// The only possible error return occurs when the pattern is malformed.
 func glob(dir, pattern string, matches []string) (m []string, e error) {
 	m = matches
 	fi, err := os.Stat(dir)
diff --git a/libgo/go/path/filepath/path.go b/libgo/go/path/filepath/path.go
index 3dc52aab467..f468d33264b 100644
--- a/libgo/go/path/filepath/path.go
+++ b/libgo/go/path/filepath/path.go
@@ -36,7 +36,7 @@ const (
 // returns the string ".".
 //
 // See also Rob Pike, ``Lexical File Names in Plan 9 or
-// Getting Dot-Dot right,''
+// Getting Dot-Dot Right,''
 // http://plan9.bell-labs.com/sys/doc/lexnames.html
 func Clean(path string) string {
 	vol := VolumeName(path)
@@ -118,7 +118,8 @@ func Clean(path string) string {
 }
 
 // ToSlash returns the result of replacing each separator character
-// in path with a slash ('/') character.
+// in path with a slash ('/') character. Multiple separators are
+// replaced by multiple slashes.
 func ToSlash(path string) string {
 	if Separator == '/' {
 		return path
@@ -127,7 +128,8 @@ func ToSlash(path string) string {
 }
 
 // FromSlash returns the result of replacing each slash ('/') character
-// in path with a separator character.
+// in path with a separator character. Multiple slashes are replaced
+// by multiple separators.
 func FromSlash(path string) string {
 	if Separator == '/' {
 		return path
@@ -135,7 +137,8 @@ func FromSlash(path string) string {
 	return strings.Replace(path, "/", string(Separator), -1)
 }
 
-// SplitList splits a list of paths joined by the OS-specific ListSeparator.
+// SplitList splits a list of paths joined by the OS-specific ListSeparator,
+// usually found in PATH or GOPATH environment variables.
 func SplitList(path string) []string {
 	if path == "" {
 		return []string{}
@@ -158,7 +161,8 @@ func Split(path string) (dir, file string) {
 }
 
 // Join joins any number of path elements into a single path, adding
-// a Separator if necessary.  All empty strings are ignored.
+// a Separator if necessary. The result is Cleaned, in particular
+// all empty strings are ignored.
 func Join(elem ...string) string {
 	for i, e := range elem {
 		if e != "" {
@@ -183,7 +187,8 @@ func Ext(path string) string {
 
 // EvalSymlinks returns the path name after the evaluation of any symbolic
 // links.
-// If path is relative it will be evaluated relative to the current directory.
+// If path is relative the result will be relative to the current directory,
+// unless one of the components is an absolute symbolic link.
 func EvalSymlinks(path string) (string, error) {
 	if runtime.GOOS == "windows" {
 		// Symlinks are not supported under windows.
@@ -443,7 +448,7 @@ func Base(path string) string {
 	return path
 }
 
-// Dir returns the all but the last element of path, typically the path's directory.
+// Dir returns all but the last element of path, typically the path's directory.
 // Trailing path separators are removed before processing.
 // If the path is empty, Dir returns ".".
 // If the path consists entirely of separators, Dir returns a single separator.
diff --git a/libgo/go/path/filepath/path_test.go b/libgo/go/path/filepath/path_test.go
index 36ab422c930..93cca1e4c2b 100644
--- a/libgo/go/path/filepath/path_test.go
+++ b/libgo/go/path/filepath/path_test.go
@@ -558,6 +558,7 @@ var EvalSymlinksTestDirs = []EvalSymlinksTest{
 	{"test/dir/link3", "../../"},
 	{"test/link1", "../test"},
 	{"test/link2", "dir"},
+	{"test/linkabs", "/"},
 }
 
 var EvalSymlinksTests = []EvalSymlinksTest{
@@ -570,6 +571,7 @@ var EvalSymlinksTests = []EvalSymlinksTest{
 	{"test/link2/..", "test"},
 	{"test/dir/link3", "."},
 	{"test/link2/link3/test", "test"},
+	{"test/linkabs", "/"},
 }
 
 var EvalSymlinksAbsWindowsTests = []EvalSymlinksTest{
@@ -628,6 +630,9 @@ func TestEvalSymlinks(t *testing.T) {
 	for _, d := range tests {
 		path := simpleJoin(tmpDir, d.path)
 		dest := simpleJoin(tmpDir, d.dest)
+		if filepath.IsAbs(d.dest) {
+			dest = d.dest
+		}
 		if p, err := filepath.EvalSymlinks(path); err != nil {
 			t.Errorf("EvalSymlinks(%q) error: %v", d.path, err)
 		} else if filepath.Clean(p) != filepath.Clean(dest) {
diff --git a/libgo/go/path/match.go b/libgo/go/path/match.go
index ba7e4de321e..8154bf60251 100644
--- a/libgo/go/path/match.go
+++ b/libgo/go/path/match.go
@@ -10,6 +10,7 @@ import (
 	"unicode/utf8"
 )
 
+// ErrBadPattern indicates a globbing pattern was malformed.
 var ErrBadPattern = errors.New("syntax error in pattern")
 
 // Match returns true if name matches the shell file name pattern.
@@ -31,7 +32,8 @@ var ErrBadPattern = errors.New("syntax error in pattern")
 //		lo '-' hi   matches character c for lo <= c <= hi
 //
 // Match requires pattern to match all of name, not just a substring.
-// The only possible error return is when pattern is malformed.
+// The only possible returned error is ErrBadPattern, when pattern
+// is malformed.
 //
 func Match(pattern, name string) (matched bool, err error) {
 Pattern:
diff --git a/libgo/go/path/path.go b/libgo/go/path/path.go
index 20d89c9ff0c..13abed0b09d 100644
--- a/libgo/go/path/path.go
+++ b/libgo/go/path/path.go
@@ -3,7 +3,7 @@
 // license that can be found in the LICENSE file.
 
 // Package path implements utility routines for manipulating slash-separated
-// filename paths.
+// paths.
 package path
 
 import (
@@ -25,7 +25,7 @@ import (
 // returns the string ".".
 //
 // See also Rob Pike, ``Lexical File Names in Plan 9 or
-// Getting Dot-Dot right,''
+// Getting Dot-Dot Right,''
 // http://plan9.bell-labs.com/sys/doc/lexnames.html
 func Clean(path string) string {
 	if path == "" {
@@ -100,17 +100,19 @@ func Clean(path string) string {
 	return string(buf[0:w])
 }
 
-// Split splits path immediately following the final path separator,
+// Split splits path immediately following the final slash.
 // separating it into a directory and file name component.
-// If there is no separator in path, Split returns an empty dir and
+// If there is no slash path, Split returns an empty dir and
 // file set to path.
+// The returned values have the property that path = dir+file.
 func Split(path string) (dir, file string) {
 	i := strings.LastIndex(path, "/")
 	return path[:i+1], path[i+1:]
 }
 
 // Join joins any number of path elements into a single path, adding a
-// separating slash if necessary.  All empty strings are ignored.
+// separating slash if necessary. The result is Cleaned; in particular,
+// all empty strings are ignored.
 func Join(elem ...string) string {
 	for i, e := range elem {
 		if e != "" {
@@ -161,11 +163,12 @@ func IsAbs(path string) bool {
 	return len(path) > 0 && path[0] == '/'
 }
 
-// Dir returns the all but the last element of path, typically the path's directory.
-// Trailing path separators are removed before processing.
+// Dir returns all but the last element of path, typically the path's directory.
+// The path is Cleaned and trailing slashes are removed before processing.
 // If the path is empty, Dir returns ".".
-// If the path consists entirely of separators, Dir returns a single separator.
-// The returned path does not end in a separator unless it is the root directory.
+// If the path consists entirely of slashes followed by non-slash bytes, Dir
+// returns a single slash. In any other case, the returned path does not end in a
+// slash.
 func Dir(path string) string {
 	dir, _ := Split(path)
 	dir = Clean(dir)
diff --git a/libgo/go/runtime/debug.go b/libgo/go/runtime/debug.go
index bd6dcc971a1..b802fc63f71 100644
--- a/libgo/go/runtime/debug.go
+++ b/libgo/go/runtime/debug.go
@@ -26,23 +26,11 @@ func GOMAXPROCS(n int) int
 // NumCPU returns the number of logical CPUs on the local machine.
 func NumCPU() int
 
-// Cgocalls returns the number of cgo calls made by the current process.
-func Cgocalls() int64
+// NumCgoCall returns the number of cgo calls made by the current process.
+func NumCgoCall() int64
 
-// Goroutines returns the number of goroutines that currently exist.
-func Goroutines() int32
-
-// Alloc allocates a block of the given size.
-// FOR TESTING AND DEBUGGING ONLY.
-func Alloc(uintptr) *byte
-
-// Free frees the block starting at the given pointer.
-// FOR TESTING AND DEBUGGING ONLY.
-func Free(*byte)
-
-// Lookup returns the base and size of the block containing the given pointer.
-// FOR TESTING AND DEBUGGING ONLY.
-func Lookup(*byte) (*byte, uintptr)
+// NumGoroutine returns the number of goroutines that currently exist.
+func NumGoroutine() int
 
 // MemProfileRate controls the fraction of memory allocations
 // that are recorded and reported in the memory profile.
@@ -101,15 +89,14 @@ func (r *MemProfileRecord) Stack() []uintptr {
 // of calling MemProfile directly.
 func MemProfile(p []MemProfileRecord, inuseZero bool) (n int, ok bool)
 
-// A ThreadProfileRecord describes the execution stack that
-// caused a new thread to be created.
-type ThreadProfileRecord struct {
+// A StackRecord describes a single execution stack.
+type StackRecord struct {
 	Stack0 [32]uintptr // stack trace for this record; ends at first 0 entry
 }
 
 // Stack returns the stack trace associated with the record,
 // a prefix of r.Stack0.
-func (r *ThreadProfileRecord) Stack() []uintptr {
+func (r *StackRecord) Stack() []uintptr {
 	for i, v := range r.Stack0 {
 		if v == 0 {
 			return r.Stack0[0:i]
@@ -118,13 +105,21 @@ func (r *ThreadProfileRecord) Stack() []uintptr {
 	return r.Stack0[0:]
 }
 
-// ThreadProfile returns n, the number of records in the current thread profile.
-// If len(p) >= n, ThreadProfile copies the profile into p and returns n, true.
-// If len(p) < n, ThreadProfile does not change p and returns n, false.
+// ThreadCreateProfile returns n, the number of records in the thread creation profile.
+// If len(p) >= n, ThreadCreateProfile copies the profile into p and returns n, true.
+// If len(p) < n, ThreadCreateProfile does not change p and returns n, false.
 //
 // Most clients should use the runtime/pprof package instead
-// of calling ThreadProfile directly.
-func ThreadProfile(p []ThreadProfileRecord) (n int, ok bool)
+// of calling ThreadCreateProfile directly.
+func ThreadCreateProfile(p []StackRecord) (n int, ok bool)
+
+// GoroutineProfile returns n, the number of records in the active goroutine stack profile.
+// If len(p) >= n, GoroutineProfile copies the profile into p and returns n, true.
+// If len(p) < n, GoroutineProfile does not change p and returns n, false.
+//
+// Most clients should use the runtime/pprof package instead
+// of calling GoroutineProfile directly.
+func GoroutineProfile(p []StackRecord) (n int, ok bool)
 
 // CPUProfile returns the next chunk of binary CPU profiling stack trace data,
 // blocking until data is available.  If profiling is turned off and all the profile
@@ -142,3 +137,9 @@ func CPUProfile() []byte
 // the testing package's -test.cpuprofile flag instead of calling
 // SetCPUProfileRate directly.
 func SetCPUProfileRate(hz int)
+
+// Stack formats a stack trace of the calling goroutine into buf
+// and returns the number of bytes written to buf.
+// If all is true, Stack formats stack traces of all other goroutines
+// into buf after the trace for the current goroutine.
+func Stack(buf []byte, all bool) int
diff --git a/libgo/go/runtime/extern.go b/libgo/go/runtime/extern.go
index eafa2f19f19..5fbfe547e46 100644
--- a/libgo/go/runtime/extern.go
+++ b/libgo/go/runtime/extern.go
@@ -68,17 +68,6 @@ func funcline_go(*Func, uintptr) (string, int)
 // mid returns the current os thread (m) id.
 func mid() uint32
 
-// Semacquire waits until *s > 0 and then atomically decrements it.
-// It is intended as a simple sleep primitive for use by the synchronization
-// library and should not be used directly.
-func Semacquire(s *uint32)
-
-// Semrelease atomically increments *s and notifies a waiting goroutine
-// if one is blocked in Semacquire.
-// It is intended as a simple wakeup primitive for use by the synchronization
-// library and should not be used directly.
-func Semrelease(s *uint32)
-
 // SetFinalizer sets the finalizer associated with x to f.
 // When the garbage collector finds an unreachable block
 // with an associated finalizer, it clears the association and runs
@@ -141,10 +130,10 @@ func Version() string {
 	return theVersion
 }
 
-// GOOS is the Go tree's operating system target:
+// GOOS is the running program's operating system target:
 // one of darwin, freebsd, linux, and so on.
 const GOOS string = theGoos
 
-// GOARCH is the Go tree's architecture target:
+// GOARCH is the running program's architecture target:
 // 386, amd64, or arm.
 const GOARCH string = theGoarch
diff --git a/libgo/go/runtime/malloc1.go b/libgo/go/runtime/malloc1.go
new file mode 100644
index 00000000000..da92f4c2fbf
--- /dev/null
+++ b/libgo/go/runtime/malloc1.go
@@ -0,0 +1,26 @@
+// Copyright 2009 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.
+
+// +build ignore
+
+// trivial malloc test
+
+package main
+
+import (
+	"flag"
+	"fmt"
+	"runtime"
+)
+
+var chatty = flag.Bool("v", false, "chatty")
+
+func main() {
+	memstats := new(runtime.MemStats)
+	runtime.Free(runtime.Alloc(1))
+	runtime.ReadMemStats(memstats)
+	if *chatty {
+		fmt.Printf("%+v %v\n", memstats, uint64(0))
+	}
+}
diff --git a/libgo/go/runtime/mallocrand.go b/libgo/go/runtime/mallocrand.go
new file mode 100644
index 00000000000..f1bcb89cfa4
--- /dev/null
+++ b/libgo/go/runtime/mallocrand.go
@@ -0,0 +1,93 @@
+// Copyright 2009 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.
+
+// +build ignore
+
+// Random malloc test.
+
+package main
+
+import (
+	"flag"
+	"math/rand"
+	"runtime"
+	"unsafe"
+)
+
+var chatty = flag.Bool("v", false, "chatty")
+
+var footprint uint64
+var allocated uint64
+
+func bigger() {
+	memstats := new(runtime.MemStats)
+	runtime.ReadMemStats(memstats)
+	if f := memstats.Sys; footprint < f {
+		footprint = f
+		if *chatty {
+			println("Footprint", footprint, " for ", allocated)
+		}
+		if footprint > 1e9 {
+			println("too big")
+			panic("fail")
+		}
+	}
+}
+
+// Prime the data structures by allocating one of
+// each block in order.  After this, there should be
+// little reason to ask for more memory from the OS.
+func prime() {
+	for i := 0; i < 16; i++ {
+		b := runtime.Alloc(1 << uint(i))
+		runtime.Free(b)
+	}
+	for i := uintptr(0); i < 256; i++ {
+		b := runtime.Alloc(i << 12)
+		runtime.Free(b)
+	}
+}
+
+func memset(b *byte, c byte, n uintptr) {
+	np := uintptr(n)
+	for i := uintptr(0); i < np; i++ {
+		*(*byte)(unsafe.Pointer(uintptr(unsafe.Pointer(b)) + i)) = c
+	}
+}
+
+func main() {
+	flag.Parse()
+	//	prime()
+	var blocks [1]struct {
+		base *byte
+		siz  uintptr
+	}
+	for i := 0; i < 1<<10; i++ {
+		if i%(1<<10) == 0 && *chatty {
+			println(i)
+		}
+		b := rand.Int() % len(blocks)
+		if blocks[b].base != nil {
+			//	println("Free", blocks[b].siz, blocks[b].base)
+			runtime.Free(blocks[b].base)
+			blocks[b].base = nil
+			allocated -= uint64(blocks[b].siz)
+			continue
+		}
+		siz := uintptr(rand.Int() >> (11 + rand.Uint32()%20))
+		base := runtime.Alloc(siz)
+		//	ptr := uintptr(syscall.BytePtr(base))+uintptr(siz/2)
+		//	obj, size, ref, ok := allocator.find(ptr)
+		//	if obj != base || *ref != 0 || !ok {
+		//		println("find", siz, obj, ref, ok)
+		//		panic("fail")
+		//	}
+		blocks[b].base = base
+		blocks[b].siz = siz
+		allocated += uint64(siz)
+		//	println("Alloc", siz, base)
+		memset(base, 0xbb, siz)
+		bigger()
+	}
+}
diff --git a/libgo/go/runtime/mallocrep.go b/libgo/go/runtime/mallocrep.go
new file mode 100644
index 00000000000..03ee71edb42
--- /dev/null
+++ b/libgo/go/runtime/mallocrep.go
@@ -0,0 +1,72 @@
+// Copyright 2009 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.
+
+// Repeated malloc test.
+
+// +build ignore
+
+package main
+
+import (
+	"flag"
+	"runtime"
+)
+
+var chatty = flag.Bool("v", false, "chatty")
+
+var oldsys uint64
+var memstats runtime.MemStats
+
+func bigger() {
+	st := &memstats
+	runtime.ReadMemStats(st)
+	if oldsys < st.Sys {
+		oldsys = st.Sys
+		if *chatty {
+			println(st.Sys, " system bytes for ", st.Alloc, " Go bytes")
+		}
+		if st.Sys > 1e9 {
+			println("too big")
+			panic("fail")
+		}
+	}
+}
+
+func main() {
+	runtime.GC()                    // clean up garbage from init
+	runtime.ReadMemStats(&memstats) // first call can do some allocations
+	runtime.MemProfileRate = 0      // disable profiler
+	stacks := memstats.Alloc        // ignore stacks
+	flag.Parse()
+	for i := 0; i < 1<<7; i++ {
+		for j := 1; j <= 1<<22; j <<= 1 {
+			if i == 0 && *chatty {
+				println("First alloc:", j)
+			}
+			if a := memstats.Alloc - stacks; a != 0 {
+				println("no allocations but stats report", a, "bytes allocated")
+				panic("fail")
+			}
+			b := runtime.Alloc(uintptr(j))
+			runtime.ReadMemStats(&memstats)
+			during := memstats.Alloc - stacks
+			runtime.Free(b)
+			runtime.ReadMemStats(&memstats)
+			if a := memstats.Alloc - stacks; a != 0 {
+				println("allocated ", j, ": wrong stats: during=", during, " after=", a, " (want 0)")
+				panic("fail")
+			}
+			bigger()
+		}
+		if i%(1<<10) == 0 && *chatty {
+			println(i)
+		}
+		if i == 0 {
+			if *chatty {
+				println("Primed", i)
+			}
+			//	runtime.frozen = true
+		}
+	}
+}
diff --git a/libgo/go/runtime/mallocrep1.go b/libgo/go/runtime/mallocrep1.go
new file mode 100644
index 00000000000..41c104c0ba7
--- /dev/null
+++ b/libgo/go/runtime/mallocrep1.go
@@ -0,0 +1,143 @@
+// Copyright 2009 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.
+
+// +build ignore
+
+// Repeated malloc test.
+
+package main
+
+import (
+	"flag"
+	"fmt"
+	"runtime"
+	"strconv"
+)
+
+var chatty = flag.Bool("v", false, "chatty")
+var reverse = flag.Bool("r", false, "reverse")
+var longtest = flag.Bool("l", false, "long test")
+
+var b []*byte
+var stats = new(runtime.MemStats)
+
+func OkAmount(size, n uintptr) bool {
+	if n < size {
+		return false
+	}
+	if size < 16*8 {
+		if n > size+16 {
+			return false
+		}
+	} else {
+		if n > size*9/8 {
+			return false
+		}
+	}
+	return true
+}
+
+func AllocAndFree(size, count int) {
+	if *chatty {
+		fmt.Printf("size=%d count=%d ...\n", size, count)
+	}
+	runtime.ReadMemStats(stats)
+	n1 := stats.Alloc
+	for i := 0; i < count; i++ {
+		b[i] = runtime.Alloc(uintptr(size))
+		base, n := runtime.Lookup(b[i])
+		if base != b[i] || !OkAmount(uintptr(size), n) {
+			println("lookup failed: got", base, n, "for", b[i])
+			panic("fail")
+		}
+		runtime.ReadMemStats(stats)
+		if stats.Sys > 1e9 {
+			println("too much memory allocated")
+			panic("fail")
+		}
+	}
+	runtime.ReadMemStats(stats)
+	n2 := stats.Alloc
+	if *chatty {
+		fmt.Printf("size=%d count=%d stats=%+v\n", size, count, *stats)
+	}
+	n3 := stats.Alloc
+	for j := 0; j < count; j++ {
+		i := j
+		if *reverse {
+			i = count - 1 - j
+		}
+		alloc := uintptr(stats.Alloc)
+		base, n := runtime.Lookup(b[i])
+		if base != b[i] || !OkAmount(uintptr(size), n) {
+			println("lookup failed: got", base, n, "for", b[i])
+			panic("fail")
+		}
+		runtime.Free(b[i])
+		runtime.ReadMemStats(stats)
+		if stats.Alloc != uint64(alloc-n) {
+			println("free alloc got", stats.Alloc, "expected", alloc-n, "after free of", n)
+			panic("fail")
+		}
+		if stats.Sys > 1e9 {
+			println("too much memory allocated")
+			panic("fail")
+		}
+	}
+	runtime.ReadMemStats(stats)
+	n4 := stats.Alloc
+
+	if *chatty {
+		fmt.Printf("size=%d count=%d stats=%+v\n", size, count, *stats)
+	}
+	if n2-n1 != n3-n4 {
+		println("wrong alloc count: ", n2-n1, n3-n4)
+		panic("fail")
+	}
+}
+
+func atoi(s string) int {
+	i, _ := strconv.Atoi(s)
+	return i
+}
+
+func main() {
+	runtime.MemProfileRate = 0 // disable profiler
+	flag.Parse()
+	b = make([]*byte, 10000)
+	if flag.NArg() > 0 {
+		AllocAndFree(atoi(flag.Arg(0)), atoi(flag.Arg(1)))
+		return
+	}
+	maxb := 1 << 22
+	if !*longtest {
+		maxb = 1 << 19
+	}
+	for j := 1; j <= maxb; j <<= 1 {
+		n := len(b)
+		max := uintptr(1 << 28)
+		if !*longtest {
+			max = uintptr(maxb)
+		}
+		if uintptr(j)*uintptr(n) > max {
+			n = int(max / uintptr(j))
+		}
+		if n < 10 {
+			n = 10
+		}
+		for m := 1; m <= n; {
+			AllocAndFree(j, m)
+			if m == n {
+				break
+			}
+			m = 5 * m / 4
+			if m < 4 {
+				m++
+			}
+			if m > n {
+				m = n
+			}
+		}
+	}
+}
diff --git a/libgo/go/runtime/mem.go b/libgo/go/runtime/mem.go
index 1301674c027..95e8aa7a533 100644
--- a/libgo/go/runtime/mem.go
+++ b/libgo/go/runtime/mem.go
@@ -17,11 +17,12 @@ type MemStats struct {
 	Frees      uint64 // number of frees
 
 	// Main allocation heap statistics.
-	HeapAlloc   uint64 // bytes allocated and still in use
-	HeapSys     uint64 // bytes obtained from system
-	HeapIdle    uint64 // bytes in idle spans
-	HeapInuse   uint64 // bytes in non-idle span
-	HeapObjects uint64 // total number of allocated objects
+	HeapAlloc    uint64 // bytes allocated and still in use
+	HeapSys      uint64 // bytes obtained from system
+	HeapIdle     uint64 // bytes in idle spans
+	HeapInuse    uint64 // bytes in non-idle span
+	HeapReleased uint64 // bytes released to the OS
+	HeapObjects  uint64 // total number of allocated objects
 
 	// Low-level fixed-size structure allocator statistics.
 	//	Inuse is bytes used now.
@@ -35,7 +36,8 @@ type MemStats struct {
 	BuckHashSys uint64 // profiling bucket hash table
 
 	// Garbage collector statistics.
-	NextGC       uint64
+	NextGC       uint64 // next run in HeapAlloc time (bytes)
+	LastGC       uint64 // last run in absolute time (ns)
 	PauseTotalNs uint64
 	PauseNs      [256]uint64 // most recent GC pause times
 	NumGC        uint32
diff --git a/libgo/go/runtime/pprof/pprof.go b/libgo/go/runtime/pprof/pprof.go
index 42f04f320a7..099bb6a92f9 100644
--- a/libgo/go/runtime/pprof/pprof.go
+++ b/libgo/go/runtime/pprof/pprof.go
@@ -10,19 +10,354 @@ package pprof
 
 import (
 	"bufio"
+	"bytes"
 	"fmt"
 	"io"
 	"runtime"
+	"sort"
+	"strings"
 	"sync"
+	"text/tabwriter"
 )
 
 // 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.
+// A Profile is a collection of stack traces showing the call sequences
+// that led to instances of a particular event, such as allocation.
+// Packages can create and maintain their own profiles; the most common
+// use is for tracking resources that must be explicitly closed, such as files
+// or network connections.
+//
+// A Profile's methods can be called from multiple goroutines simultaneously.
+//
+// Each Profile has a unique name.  A few profiles are predefined:
+//
+//	goroutine    - stack traces of all current goroutines
+//	heap         - a sampling of all heap allocations
+//	threadcreate - stack traces that led to the creation of new OS threads
+//
+// These predefine profiles maintain themselves and panic on an explicit
+// Add or Remove method call.
+//
+// The CPU profile is not available as a Profile.  It has a special API,
+// the StartCPUProfile and StopCPUProfile functions, because it streams
+// output to a writer during profiling.
+//
+type Profile struct {
+	name  string
+	mu    sync.Mutex
+	m     map[interface{}][]uintptr
+	count func() int
+	write func(io.Writer, int) error
+}
+
+// profiles records all registered profiles.
+var profiles struct {
+	mu sync.Mutex
+	m  map[string]*Profile
+}
+
+var goroutineProfile = &Profile{
+	name:  "goroutine",
+	count: countGoroutine,
+	write: writeGoroutine,
+}
+
+var threadcreateProfile = &Profile{
+	name:  "threadcreate",
+	count: countThreadCreate,
+	write: writeThreadCreate,
+}
+
+var heapProfile = &Profile{
+	name:  "heap",
+	count: countHeap,
+	write: writeHeap,
+}
+
+func lockProfiles() {
+	profiles.mu.Lock()
+	if profiles.m == nil {
+		// Initial built-in profiles.
+		profiles.m = map[string]*Profile{
+			"goroutine":    goroutineProfile,
+			"threadcreate": threadcreateProfile,
+			"heap":         heapProfile,
+		}
+	}
+}
+
+func unlockProfiles() {
+	profiles.mu.Unlock()
+}
+
+// NewProfile creates a new profile with the given name.
+// If a profile with that name already exists, NewProfile panics.
+// The convention is to use a 'import/path.' prefix to create
+// separate name spaces for each package.
+func NewProfile(name string) *Profile {
+	lockProfiles()
+	defer unlockProfiles()
+	if name == "" {
+		panic("pprof: NewProfile with empty name")
+	}
+	if profiles.m[name] != nil {
+		panic("pprof: NewProfile name already in use: " + name)
+	}
+	p := &Profile{
+		name: name,
+		m:    map[interface{}][]uintptr{},
+	}
+	profiles.m[name] = p
+	return p
+}
+
+// Lookup returns the profile with the given name, or nil if no such profile exists.
+func Lookup(name string) *Profile {
+	lockProfiles()
+	defer unlockProfiles()
+	return profiles.m[name]
+}
+
+// Profiles returns a slice of all the known profiles, sorted by name.
+func Profiles() []*Profile {
+	lockProfiles()
+	defer unlockProfiles()
+
+	var all []*Profile
+	for _, p := range profiles.m {
+		all = append(all, p)
+	}
+
+	sort.Sort(byName(all))
+	return all
+}
+
+type byName []*Profile
+
+func (x byName) Len() int           { return len(x) }
+func (x byName) Swap(i, j int)      { x[i], x[j] = x[j], x[i] }
+func (x byName) Less(i, j int) bool { return x[i].name < x[j].name }
+
+// Name returns this profile's name, which can be passed to Lookup to reobtain the profile.
+func (p *Profile) Name() string {
+	return p.name
+}
+
+// Count returns the number of execution stacks currently in the profile.
+func (p *Profile) Count() int {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	if p.count != nil {
+		return p.count()
+	}
+	return len(p.m)
+}
+
+// Add adds the current execution stack to the profile, associated with value.
+// Add stores value in an internal map, so value must be suitable for use as 
+// a map key and will not be garbage collected until the corresponding
+// call to Remove.  Add panics if the profile already contains a stack for value.
+//
+// The skip parameter has the same meaning as runtime.Caller's skip
+// and controls where the stack trace begins.  Passing skip=0 begins the
+// trace in the function calling Add.  For example, given this
+// execution stack:
+//
+//	Add
+//	called from rpc.NewClient
+//	called from mypkg.Run
+//	called from main.main
+//
+// Passing skip=0 begins the stack trace at the call to Add inside rpc.NewClient.
+// Passing skip=1 begins the stack trace at the call to NewClient inside mypkg.Run.
+//
+func (p *Profile) Add(value interface{}, skip int) {
+	if p.name == "" {
+		panic("pprof: use of uninitialized Profile")
+	}
+	if p.write != nil {
+		panic("pprof: Add called on built-in Profile " + p.name)
+	}
+
+	stk := make([]uintptr, 32)
+	n := runtime.Callers(skip+1, stk[:])
+
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	if p.m[value] != nil {
+		panic("pprof: Profile.Add of duplicate value")
+	}
+	p.m[value] = stk[:n]
+}
+
+// Remove removes the execution stack associated with value from the profile.
+// It is a no-op if the value is not in the profile.
+func (p *Profile) Remove(value interface{}) {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	delete(p.m, value)
+}
+
+// WriteTo writes a pprof-formatted snapshot of the profile to w.
+// If a write to w returns an error, WriteTo returns that error.
+// Otherwise, WriteTo returns nil.
+//
+// The debug parameter enables additional output.
+// Passing debug=0 prints only the hexadecimal addresses that pprof needs.
+// Passing debug=1 adds comments translating addresses to function names
+// and line numbers, so that a programmer can read the profile without tools.
+//
+// The predefined profiles may assign meaning to other debug values;
+// for example, when printing the "goroutine" profile, debug=2 means to
+// print the goroutine stacks in the same form that a Go program uses
+// when dying due to an unrecovered panic.
+func (p *Profile) WriteTo(w io.Writer, debug int) error {
+	if p.name == "" {
+		panic("pprof: use of zero Profile")
+	}
+	if p.write != nil {
+		return p.write(w, debug)
+	}
+
+	// Obtain consistent snapshot under lock; then process without lock.
+	var all [][]uintptr
+	p.mu.Lock()
+	for _, stk := range p.m {
+		all = append(all, stk)
+	}
+	p.mu.Unlock()
+
+	// Map order is non-deterministic; make output deterministic.
+	sort.Sort(stackProfile(all))
+
+	return printCountProfile(w, debug, p.name, stackProfile(all))
+}
+
+type stackProfile [][]uintptr
+
+func (x stackProfile) Len() int              { return len(x) }
+func (x stackProfile) Stack(i int) []uintptr { return x[i] }
+func (x stackProfile) Swap(i, j int)         { x[i], x[j] = x[j], x[i] }
+func (x stackProfile) Less(i, j int) bool {
+	t, u := x[i], x[j]
+	for k := 0; k < len(t) && k < len(u); k++ {
+		if t[k] != u[k] {
+			return t[k] < u[k]
+		}
+	}
+	return len(t) < len(u)
+}
+
+// A countProfile is a set of stack traces to be printed as counts
+// grouped by stack trace.  There are multiple implementations:
+// all that matters is that we can find out how many traces there are
+// and obtain each trace in turn.
+type countProfile interface {
+	Len() int
+	Stack(i int) []uintptr
+}
+
+// printCountProfile prints a countProfile at the specified debug level.
+func printCountProfile(w io.Writer, debug int, name string, p countProfile) error {
+	b := bufio.NewWriter(w)
+	var tw *tabwriter.Writer
+	w = b
+	if debug > 0 {
+		tw = tabwriter.NewWriter(w, 1, 8, 1, '\t', 0)
+		w = tw
+	}
+
+	fmt.Fprintf(w, "%s profile: total %d\n", name, p.Len())
+
+	// Build count of each stack.
+	var buf bytes.Buffer
+	key := func(stk []uintptr) string {
+		buf.Reset()
+		fmt.Fprintf(&buf, "@")
+		for _, pc := range stk {
+			fmt.Fprintf(&buf, " %#x", pc)
+		}
+		return buf.String()
+	}
+	m := map[string]int{}
+	n := p.Len()
+	for i := 0; i < n; i++ {
+		m[key(p.Stack(i))]++
+	}
+
+	// Print stacks, listing count on first occurrence of a unique stack.
+	for i := 0; i < n; i++ {
+		stk := p.Stack(i)
+		s := key(stk)
+		if count := m[s]; count != 0 {
+			fmt.Fprintf(w, "%d %s\n", count, s)
+			if debug > 0 {
+				printStackRecord(w, stk, false)
+			}
+			delete(m, s)
+		}
+	}
+
+	if tw != nil {
+		tw.Flush()
+	}
+	return b.Flush()
+}
+
+// printStackRecord prints the function + source line information
+// for a single stack trace.
+func printStackRecord(w io.Writer, stk []uintptr, allFrames bool) {
+	show := allFrames
+	for _, pc := range stk {
+		f := runtime.FuncForPC(pc)
+		if f == nil {
+			show = true
+			fmt.Fprintf(w, "#\t%#x\n", pc)
+		} else {
+			file, line := f.FileLine(pc)
+			name := f.Name()
+			// Hide runtime.goexit and any runtime functions at the beginning.
+			// This is useful mainly for allocation traces.
+			if name == "runtime.goexit" || !show && strings.HasPrefix(name, "runtime.") {
+				continue
+			}
+			show = true
+			fmt.Fprintf(w, "#\t%#x\t%s+%#x\t%s:%d\n", pc, f.Name(), pc-f.Entry(), file, line)
+		}
+	}
+	if !show {
+		// We didn't print anything; do it again,
+		// and this time include runtime functions.
+		printStackRecord(w, stk, true)
+		return
+	}
+	fmt.Fprintf(w, "\n")
+}
+
+// Interface to system profiles.
+
+type byInUseBytes []runtime.MemProfileRecord
+
+func (x byInUseBytes) Len() int           { return len(x) }
+func (x byInUseBytes) Swap(i, j int)      { x[i], x[j] = x[j], x[i] }
+func (x byInUseBytes) Less(i, j int) bool { return x[i].InUseBytes() > x[j].InUseBytes() }
+
+// WriteHeapProfile is shorthand for Lookup("heap").WriteTo(w, 0).
+// It is preserved for backwards compatibility.
 func WriteHeapProfile(w io.Writer) error {
+	return writeHeap(w, 0)
+}
+
+// countHeap returns the number of records in the heap profile.
+func countHeap() int {
+	n, _ := runtime.MemProfile(nil, false)
+	return n
+}
+
+// writeHeapProfile writes the current runtime heap profile to w.
+func writeHeap(w io.Writer, debug int) error {
 	// Find out how many records there are (MemProfile(nil, false)),
 	// allocate that many records, and get the data.
 	// There's a race—more records might be added between
@@ -44,6 +379,16 @@ func WriteHeapProfile(w io.Writer) error {
 		// Profile grew; try again.
 	}
 
+	sort.Sort(byInUseBytes(p))
+
+	b := bufio.NewWriter(w)
+	var tw *tabwriter.Writer
+	w = b
+	if debug > 0 {
+		tw = tabwriter.NewWriter(w, 1, 8, 1, '\t', 0)
+		w = tw
+	}
+
 	var total runtime.MemProfileRecord
 	for i := range p {
 		r := &p[i]
@@ -56,78 +401,120 @@ func WriteHeapProfile(w io.Writer) error {
 	// Technically the rate is MemProfileRate not 2*MemProfileRate,
 	// but early versions of the C++ heap profiler reported 2*MemProfileRate,
 	// so that's what pprof has come to expect.
-	b := bufio.NewWriter(w)
-	fmt.Fprintf(b, "heap profile: %d: %d [%d: %d] @ heap/%d\n",
+	fmt.Fprintf(w, "heap profile: %d: %d [%d: %d] @ heap/%d\n",
 		total.InUseObjects(), total.InUseBytes(),
 		total.AllocObjects, total.AllocBytes,
 		2*runtime.MemProfileRate)
 
 	for i := range p {
 		r := &p[i]
-		fmt.Fprintf(b, "%d: %d [%d: %d] @",
+		fmt.Fprintf(w, "%d: %d [%d: %d] @",
 			r.InUseObjects(), r.InUseBytes(),
 			r.AllocObjects, r.AllocBytes)
 		for _, pc := range r.Stack() {
-			fmt.Fprintf(b, " %#x", pc)
+			fmt.Fprintf(w, " %#x", pc)
+		}
+		fmt.Fprintf(w, "\n")
+		if debug > 0 {
+			printStackRecord(w, r.Stack(), false)
 		}
-		fmt.Fprintf(b, "\n")
 	}
 
 	// Print memstats information too.
-	// Pprof will ignore, but useful for people.
-	s := new(runtime.MemStats)
-	runtime.ReadMemStats(s)
-	fmt.Fprintf(b, "\n# runtime.MemStats\n")
-	fmt.Fprintf(b, "# Alloc = %d\n", s.Alloc)
-	fmt.Fprintf(b, "# TotalAlloc = %d\n", s.TotalAlloc)
-	fmt.Fprintf(b, "# Sys = %d\n", s.Sys)
-	fmt.Fprintf(b, "# Lookups = %d\n", s.Lookups)
-	fmt.Fprintf(b, "# Mallocs = %d\n", s.Mallocs)
-
-	fmt.Fprintf(b, "# HeapAlloc = %d\n", s.HeapAlloc)
-	fmt.Fprintf(b, "# HeapSys = %d\n", s.HeapSys)
-	fmt.Fprintf(b, "# HeapIdle = %d\n", s.HeapIdle)
-	fmt.Fprintf(b, "# HeapInuse = %d\n", s.HeapInuse)
-
-	fmt.Fprintf(b, "# Stack = %d / %d\n", s.StackInuse, s.StackSys)
-	fmt.Fprintf(b, "# MSpan = %d / %d\n", s.MSpanInuse, s.MSpanSys)
-	fmt.Fprintf(b, "# MCache = %d / %d\n", s.MCacheInuse, s.MCacheSys)
-	fmt.Fprintf(b, "# BuckHashSys = %d\n", s.BuckHashSys)
-
-	fmt.Fprintf(b, "# NextGC = %d\n", s.NextGC)
-	fmt.Fprintf(b, "# PauseNs = %d\n", s.PauseNs)
-	fmt.Fprintf(b, "# NumGC = %d\n", s.NumGC)
-	fmt.Fprintf(b, "# EnableGC = %v\n", s.EnableGC)
-	fmt.Fprintf(b, "# DebugGC = %v\n", s.DebugGC)
-
-	fmt.Fprintf(b, "# BySize = Size * (Active = Mallocs - Frees)\n")
-	fmt.Fprintf(b, "# (Excluding large blocks.)\n")
-	for _, t := range s.BySize {
-		if t.Mallocs > 0 {
-			fmt.Fprintf(b, "#   %d * (%d = %d - %d)\n", t.Size, t.Mallocs-t.Frees, t.Mallocs, t.Frees)
-		}
+	// Pprof will ignore, but useful for people
+	if debug > 0 {
+		s := new(runtime.MemStats)
+		runtime.ReadMemStats(s)
+		fmt.Fprintf(w, "\n# runtime.MemStats\n")
+		fmt.Fprintf(w, "# Alloc = %d\n", s.Alloc)
+		fmt.Fprintf(w, "# TotalAlloc = %d\n", s.TotalAlloc)
+		fmt.Fprintf(w, "# Sys = %d\n", s.Sys)
+		fmt.Fprintf(w, "# Lookups = %d\n", s.Lookups)
+		fmt.Fprintf(w, "# Mallocs = %d\n", s.Mallocs)
+
+		fmt.Fprintf(w, "# HeapAlloc = %d\n", s.HeapAlloc)
+		fmt.Fprintf(w, "# HeapSys = %d\n", s.HeapSys)
+		fmt.Fprintf(w, "# HeapIdle = %d\n", s.HeapIdle)
+		fmt.Fprintf(w, "# HeapInuse = %d\n", s.HeapInuse)
+
+		fmt.Fprintf(w, "# Stack = %d / %d\n", s.StackInuse, s.StackSys)
+		fmt.Fprintf(w, "# MSpan = %d / %d\n", s.MSpanInuse, s.MSpanSys)
+		fmt.Fprintf(w, "# MCache = %d / %d\n", s.MCacheInuse, s.MCacheSys)
+		fmt.Fprintf(w, "# BuckHashSys = %d\n", s.BuckHashSys)
+
+		fmt.Fprintf(w, "# NextGC = %d\n", s.NextGC)
+		fmt.Fprintf(w, "# PauseNs = %d\n", s.PauseNs)
+		fmt.Fprintf(w, "# NumGC = %d\n", s.NumGC)
+		fmt.Fprintf(w, "# EnableGC = %v\n", s.EnableGC)
+		fmt.Fprintf(w, "# DebugGC = %v\n", s.DebugGC)
+	}
+
+	if tw != nil {
+		tw.Flush()
 	}
 	return b.Flush()
 }
 
-// WriteThreadProfile writes a pprof-formatted thread creation profile to w.
-// If a write to w returns an error, WriteThreadProfile returns that error.
-// Otherwise, WriteThreadProfile returns nil.
-func WriteThreadProfile(w io.Writer) error {
-	// Find out how many records there are (ThreadProfile(nil)),
+// countThreadCreate returns the size of the current ThreadCreateProfile.
+func countThreadCreate() int {
+	n, _ := runtime.ThreadCreateProfile(nil)
+	return n
+}
+
+// writeThreadCreate writes the current runtime ThreadCreateProfile to w.
+func writeThreadCreate(w io.Writer, debug int) error {
+	return writeRuntimeProfile(w, debug, "threadcreate", runtime.ThreadCreateProfile)
+}
+
+// countGoroutine returns the number of goroutines.
+func countGoroutine() int {
+	return runtime.NumGoroutine()
+}
+
+// writeGoroutine writes the current runtime GoroutineProfile to w.
+func writeGoroutine(w io.Writer, debug int) error {
+	if debug >= 2 {
+		return writeGoroutineStacks(w)
+	}
+	return writeRuntimeProfile(w, debug, "goroutine", runtime.GoroutineProfile)
+}
+
+func writeGoroutineStacks(w io.Writer) error {
+	// We don't know how big the buffer needs to be to collect
+	// all the goroutines.  Start with 1 MB and try a few times, doubling each time.
+	// Give up and use a truncated trace if 64 MB is not enough.
+	buf := make([]byte, 1<<20)
+	for i := 0; ; i++ {
+		n := runtime.Stack(buf, true)
+		if n < len(buf) {
+			buf = buf[:n]
+			break
+		}
+		if len(buf) >= 64<<20 {
+			// Filled 64 MB - stop there.
+			break
+		}
+		buf = make([]byte, 2*len(buf))
+	}
+	_, err := w.Write(buf)
+	return err
+}
+
+func writeRuntimeProfile(w io.Writer, debug int, name string, fetch func([]runtime.StackRecord) (int, bool)) error {
+	// Find out how many records there are (fetch(nil)),
 	// allocate that many records, and get the data.
-	// There's a race—more records (threads) might be added between
+	// There's a race—more records might be added between
 	// the two calls—so allocate a few extra records for safety
 	// and also try again if we're very unlucky.
 	// The loop should only execute one iteration in the common case.
-	var p []runtime.ThreadProfileRecord
-	n, ok := runtime.ThreadProfile(nil)
+	var p []runtime.StackRecord
+	n, ok := fetch(nil)
 	for {
 		// Allocate room for a slightly bigger profile,
 		// in case a few more entries have been added
 		// since the call to ThreadProfile.
-		p = make([]runtime.ThreadProfileRecord, n+10)
-		n, ok = runtime.ThreadProfile(p)
+		p = make([]runtime.StackRecord, n+10)
+		n, ok = fetch(p)
 		if ok {
 			p = p[0:n]
 			break
@@ -135,19 +522,14 @@ func WriteThreadProfile(w io.Writer) error {
 		// Profile grew; try again.
 	}
 
-	b := bufio.NewWriter(w)
-	fmt.Fprintf(b, "thread creation profile: %d threads\n", n)
-	for i := range p {
-		r := &p[i]
-		fmt.Fprintf(b, "@")
-		for _, pc := range r.Stack() {
-			fmt.Fprintf(b, " %#x", pc)
-		}
-		fmt.Fprintf(b, "\n")
-	}
-	return b.Flush()
+	return printCountProfile(w, debug, name, runtimeProfile(p))
 }
 
+type runtimeProfile []runtime.StackRecord
+
+func (p runtimeProfile) Len() int              { return len(p) }
+func (p runtimeProfile) Stack(i int) []uintptr { return p[i].Stack() }
+
 var cpu struct {
 	sync.Mutex
 	profiling bool
diff --git a/libgo/go/sort/example_interface_test.go b/libgo/go/sort/example_interface_test.go
new file mode 100644
index 00000000000..4c88821be7c
--- /dev/null
+++ b/libgo/go/sort/example_interface_test.go
@@ -0,0 +1,77 @@
+// 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.
+
+package sort_test
+
+import (
+	"fmt"
+	"sort"
+)
+
+type Grams int
+
+func (g Grams) String() string { return fmt.Sprintf("%dg", int(g)) }
+
+type Organ struct {
+	Name   string
+	Weight Grams
+}
+
+type Organs []*Organ
+
+func (s Organs) Len() int      { return len(s) }
+func (s Organs) Swap(i, j int) { s[i], s[j] = s[j], s[i] }
+
+// ByName implements sort.Interface by providing Less and using the Len and
+// Swap methods of the embedded Organs value.
+type ByName struct{ Organs }
+
+func (s ByName) Less(i, j int) bool { return s.Organs[i].Name < s.Organs[j].Name }
+
+// ByWeight implements sort.Interface by providing Less and using the Len and
+// Swap methods of the embedded Organs value.
+type ByWeight struct{ Organs }
+
+func (s ByWeight) Less(i, j int) bool { return s.Organs[i].Weight < s.Organs[j].Weight }
+
+func ExampleInterface() {
+	s := []*Organ{
+		{"brain", 1340},
+		{"heart", 290},
+		{"liver", 1494},
+		{"pancreas", 131},
+		{"prostate", 62},
+		{"spleen", 162},
+	}
+
+	sort.Sort(ByWeight{s})
+	fmt.Println("Organs by weight:")
+	printOrgans(s)
+
+	sort.Sort(ByName{s})
+	fmt.Println("Organs by name:")
+	printOrgans(s)
+
+	// Output:
+	// Organs by weight:
+	// prostate (62g)
+	// pancreas (131g)
+	// spleen   (162g)
+	// heart    (290g)
+	// brain    (1340g)
+	// liver    (1494g)
+	// Organs by name:
+	// brain    (1340g)
+	// heart    (290g)
+	// liver    (1494g)
+	// pancreas (131g)
+	// prostate (62g)
+	// spleen   (162g)
+}
+
+func printOrgans(s []*Organ) {
+	for _, o := range s {
+		fmt.Printf("%-8s (%v)\n", o.Name, o.Weight)
+	}
+}
diff --git a/libgo/go/sort/example_reverse_test.go b/libgo/go/sort/example_reverse_test.go
new file mode 100644
index 00000000000..7c7f05bf3a2
--- /dev/null
+++ b/libgo/go/sort/example_reverse_test.go
@@ -0,0 +1,30 @@
+// 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.
+
+package sort_test
+
+import (
+	"fmt"
+	"sort"
+)
+
+// Reverse embeds a sort.Interface value and implements a reverse sort over
+// that value.
+type Reverse struct {
+	// This embedded Interface permits Reverse to use the methods of
+	// another Interface implementation.
+	sort.Interface
+}
+
+// Less returns the opposite of the embedded implementation's Less method.
+func (r Reverse) Less(i, j int) bool {
+	return r.Interface.Less(j, i)
+}
+
+func ExampleInterface_reverse() {
+	s := []int{5, 2, 6, 3, 1, 4} // unsorted
+	sort.Sort(Reverse{sort.IntSlice(s)})
+	fmt.Println(s)
+	// Output: [6 5 4 3 2 1]
+}
diff --git a/libgo/go/sort/example_test.go b/libgo/go/sort/example_test.go
index 2224db7e13c..f57d02546f7 100644
--- a/libgo/go/sort/example_test.go
+++ b/libgo/go/sort/example_test.go
@@ -9,9 +9,9 @@ import (
 	"sort"
 )
 
-// [1 2 3 4 5 6]
 func ExampleInts() {
 	s := []int{5, 2, 6, 3, 1, 4} // unsorted
 	sort.Ints(s)
 	fmt.Println(s)
+	// Output: [1 2 3 4 5 6]
 }
diff --git a/libgo/go/strconv/atof.go b/libgo/go/strconv/atof.go
index cd3031b0e61..d99117bed1d 100644
--- a/libgo/go/strconv/atof.go
+++ b/libgo/go/strconv/atof.go
@@ -13,6 +13,7 @@ package strconv
 //   3) Multiply by 2^precision and round to get mantissa.
 
 import "math"
+import "runtime"
 
 var optimize = true // can change for testing
 
@@ -300,6 +301,11 @@ func (d *decimal) atof64() (f float64, ok bool) {
 	if d.nd > 15 {
 		return
 	}
+	// gccgo gets this wrong on 32-bit i386 when not using -msse.
+	// See TestRoundTrip in atof_test.go for a test case.
+	if runtime.GOARCH == "386" {
+		return
+	}
 	switch {
 	case d.dp == d.nd: // int
 		f := d.atof64int()
diff --git a/libgo/go/strconv/itoa_test.go b/libgo/go/strconv/itoa_test.go
index bac23e6ea67..63d2fa44e02 100644
--- a/libgo/go/strconv/itoa_test.go
+++ b/libgo/go/strconv/itoa_test.go
@@ -127,6 +127,7 @@ func TestUitoa(t *testing.T) {
 }
 
 func numAllocations(f func()) int {
+	runtime.GC()
 	memstats := new(runtime.MemStats)
 	runtime.ReadMemStats(memstats)
 	n0 := memstats.Mallocs
diff --git a/libgo/go/strings/example_test.go b/libgo/go/strings/example_test.go
index 5ef0b93d15e..0b583411331 100644
--- a/libgo/go/strings/example_test.go
+++ b/libgo/go/strings/example_test.go
@@ -9,134 +9,142 @@ import (
 	"strings"
 )
 
-// Fields are: ["foo" "bar" "baz"]
 func ExampleFields() {
 	fmt.Printf("Fields are: %q", strings.Fields("  foo bar  baz   "))
+	// Output: Fields are: ["foo" "bar" "baz"]
 }
 
-// true
-// false
-// true
-// true
 func ExampleContains() {
 	fmt.Println(strings.Contains("seafood", "foo"))
 	fmt.Println(strings.Contains("seafood", "bar"))
 	fmt.Println(strings.Contains("seafood", ""))
 	fmt.Println(strings.Contains("", ""))
+	// Output:
+	// true
+	// false
+	// true
+	// true
 }
 
-// false
-// true
-// false
-// false
 func ExampleContainsAny() {
 	fmt.Println(strings.ContainsAny("team", "i"))
 	fmt.Println(strings.ContainsAny("failure", "u & i"))
 	fmt.Println(strings.ContainsAny("foo", ""))
 	fmt.Println(strings.ContainsAny("", ""))
-
+	// Output:
+	// false
+	// true
+	// false
+	// false
 }
 
-// 3
-// 5
 func ExampleCount() {
 	fmt.Println(strings.Count("cheese", "e"))
 	fmt.Println(strings.Count("five", "")) // before & after each rune
+	// Output:
+	// 3
+	// 5
 }
 
-// true
 func ExampleEqualFold() {
 	fmt.Println(strings.EqualFold("Go", "go"))
+	// Output: true
 }
 
-// 4
-// -1
 func ExampleIndex() {
 	fmt.Println(strings.Index("chicken", "ken"))
 	fmt.Println(strings.Index("chicken", "dmr"))
+	// Output:
+	// 4
+	// -1
 }
 
-// 4
-// -1
 func ExampleRune() {
 	fmt.Println(strings.IndexRune("chicken", 'k'))
 	fmt.Println(strings.IndexRune("chicken", 'd'))
+	// Output:
+	// 4
+	// -1
 }
 
-// 0
-// 3
-// -1
 func ExampleLastIndex() {
 	fmt.Println(strings.Index("go gopher", "go"))
 	fmt.Println(strings.LastIndex("go gopher", "go"))
 	fmt.Println(strings.LastIndex("go gopher", "rodent"))
+	// Output:
+	// 0
+	// 3
+	// -1
 }
 
-// foo, bar, baz
 func ExampleJoin() {
 	s := []string{"foo", "bar", "baz"}
 	fmt.Println(strings.Join(s, ", "))
+	// Output: foo, bar, baz
 }
 
-// banana
 func ExampleRepeat() {
 	fmt.Println("ba" + strings.Repeat("na", 2))
+	// Output: banana
 }
 
-// oinky oinky oink
-// moo moo moo
 func ExampleReplace() {
 	fmt.Println(strings.Replace("oink oink oink", "k", "ky", 2))
 	fmt.Println(strings.Replace("oink oink oink", "oink", "moo", -1))
+	// Output:
+	// oinky oinky oink
+	// moo moo moo
 }
 
-// ["a" "b" "c"]
-// ["" "man " "plan " "canal panama"]
-// [" " "x" "y" "z" " "]
-// [""]
 func ExampleSplit() {
 	fmt.Printf("%q\n", strings.Split("a,b,c", ","))
 	fmt.Printf("%q\n", strings.Split("a man a plan a canal panama", "a "))
 	fmt.Printf("%q\n", strings.Split(" xyz ", ""))
 	fmt.Printf("%q\n", strings.Split("", "Bernardo O'Higgins"))
+	// Output:
+	// ["a" "b" "c"]
+	// ["" "man " "plan " "canal panama"]
+	// [" " "x" "y" "z" " "]
+	// [""]
 }
 
-// ["a" "b,c"]
-// [] (nil = true)
 func ExampleSplitN() {
 	fmt.Printf("%q\n", strings.SplitN("a,b,c", ",", 2))
 	z := strings.SplitN("a,b,c", ",", 0)
 	fmt.Printf("%q (nil = %v)\n", z, z == nil)
+	// Output:
+	// ["a" "b,c"]
+	// [] (nil = true)
 }
 
-// ["a," "b," "c"]
 func ExampleSplitAfter() {
 	fmt.Printf("%q\n", strings.SplitAfter("a,b,c", ","))
+	// Output: ["a," "b," "c"]
 }
 
-// ["a," "b,c"]
 func ExampleSplitAfterN() {
 	fmt.Printf("%q\n", strings.SplitAfterN("a,b,c", ",", 2))
+	// Output: ["a," "b,c"]
 }
 
-// Her Royal Highness
 func ExampleTitle() {
 	fmt.Println(strings.Title("her royal highness"))
+	// Output: Her Royal Highness
 }
 
-// LOUD NOISES
-// ХЛЕБ
 func ExampleToTitle() {
 	fmt.Println(strings.ToTitle("loud noises"))
 	fmt.Println(strings.ToTitle("хлеб"))
+	// Output:
+	// LOUD NOISES
+	// ХЛЕБ
 }
 
-// [Achtung]
 func ExampleTrim() {
-	fmt.Printf("[%s]", strings.Trim(" !!! Achtung !!! ", "! "))
+	fmt.Printf("[%q]", strings.Trim(" !!! Achtung !!! ", "! "))
+	// Output: ["Achtung"]
 }
 
-// 'Gjnf oevyyvt naq gur fyvgul tbcure...
 func ExampleMap() {
 	rot13 := func(r rune) rune {
 		switch {
@@ -148,25 +156,26 @@ func ExampleMap() {
 		return r
 	}
 	fmt.Println(strings.Map(rot13, "'Twas brillig and the slithy gopher..."))
+	// Output: 'Gjnf oevyyvt naq gur fyvgul tbcure...
 }
 
-// a lone gopher
 func ExampleTrimSpace() {
 	fmt.Println(strings.TrimSpace(" \t\n a lone gopher \n\t\r\n"))
+	// Output: a lone gopher
 }
 
-// This is &lt;b&gt;HTML&lt;/b&gt;!
 func ExampleNewReplacer() {
 	r := strings.NewReplacer("<", "&lt;", ">", "&gt;")
 	fmt.Println(r.Replace("This is <b>HTML</b>!"))
+	// Output: This is &lt;b&gt;HTML&lt;/b&gt;!
 }
 
-// GOPHER
 func ExampleToUpper() {
 	fmt.Println(strings.ToUpper("Gopher"))
+	// Output: GOPHER
 }
 
-// gopher
 func ExampleToLower() {
 	fmt.Println(strings.ToLower("Gopher"))
+	// Output: gopher
 }
diff --git a/libgo/go/sync/cond.go b/libgo/go/sync/cond.go
index 75494b53536..1fc3deaf1e0 100644
--- a/libgo/go/sync/cond.go
+++ b/libgo/go/sync/cond.go
@@ -4,8 +4,6 @@
 
 package sync
 
-import "runtime"
-
 // Cond implements a condition variable, a rendezvous point
 // for goroutines waiting for or announcing the occurrence
 // of an event.
@@ -43,9 +41,10 @@ func NewCond(l Locker) *Cond {
 
 // Wait atomically unlocks c.L and suspends execution
 // of the calling goroutine.  After later resuming execution,
-// Wait locks c.L before returning.
+// Wait locks c.L before returning.  Unlike in other systems,
+// Wait cannot return unless awoken by Broadcast or Signal.
 //
-// Because L is not locked when Wait first resumes, the caller
+// Because c.L is not locked when Wait first resumes, the caller
 // typically cannot assume that the condition is true when
 // Wait returns.  Instead, the caller should Wait in a loop:
 //
@@ -65,7 +64,7 @@ func (c *Cond) Wait() {
 	c.newWaiters++
 	c.m.Unlock()
 	c.L.Unlock()
-	runtime.Semacquire(s)
+	runtime_Semacquire(s)
 	c.L.Lock()
 }
 
@@ -84,7 +83,7 @@ func (c *Cond) Signal() {
 	}
 	if c.oldWaiters > 0 {
 		c.oldWaiters--
-		runtime.Semrelease(c.oldSema)
+		runtime_Semrelease(c.oldSema)
 	}
 	c.m.Unlock()
 }
@@ -98,13 +97,13 @@ func (c *Cond) Broadcast() {
 	// Wake both generations.
 	if c.oldWaiters > 0 {
 		for i := 0; i < c.oldWaiters; i++ {
-			runtime.Semrelease(c.oldSema)
+			runtime_Semrelease(c.oldSema)
 		}
 		c.oldWaiters = 0
 	}
 	if c.newWaiters > 0 {
 		for i := 0; i < c.newWaiters; i++ {
-			runtime.Semrelease(c.newSema)
+			runtime_Semrelease(c.newSema)
 		}
 		c.newWaiters = 0
 		c.newSema = nil
diff --git a/libgo/go/sync/example_test.go b/libgo/go/sync/example_test.go
new file mode 100644
index 00000000000..1424b1e79e6
--- /dev/null
+++ b/libgo/go/sync/example_test.go
@@ -0,0 +1,34 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package sync_test
+
+import (
+	"net/http"
+	"sync"
+)
+
+// This example fetches several URLs concurrently,
+// using a WaitGroup to block until all the fetches are complete.
+func ExampleWaitGroup() {
+	var wg sync.WaitGroup
+	var urls = []string{
+		"http://www.golang.org/",
+		"http://www.google.com/",
+		"http://www.somestupidname.com/",
+	}
+	for _, url := range urls {
+		// Increment the WaitGroup counter.
+		wg.Add(1)
+		// Launch a goroutine to fetch the URL.
+		go func(url string) {
+			// Fetch the URL.
+			http.Get(url)
+			// Decrement the counter.
+			wg.Done()
+		}(url)
+	}
+	// Wait for all HTTP fetches to complete.
+	wg.Wait()
+}
diff --git a/libgo/go/sync/export_test.go b/libgo/go/sync/export_test.go
new file mode 100644
index 00000000000..fa5983a2d1e
--- /dev/null
+++ b/libgo/go/sync/export_test.go
@@ -0,0 +1,9 @@
+// Copyright 2012 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package sync
+
+// Export for testing.
+var Runtime_Semacquire = runtime_Semacquire
+var Runtime_Semrelease = runtime_Semrelease
diff --git a/libgo/go/sync/mutex.go b/libgo/go/sync/mutex.go
index 4fc02743c6e..9494cc3f826 100644
--- a/libgo/go/sync/mutex.go
+++ b/libgo/go/sync/mutex.go
@@ -10,10 +10,7 @@
 // Values containing the types defined in this package should not be copied.
 package sync
 
-import (
-	"runtime"
-	"sync/atomic"
-)
+import "sync/atomic"
 
 // A Mutex is a mutual exclusion lock.
 // Mutexes can be created as part of other structures;
@@ -60,7 +57,7 @@ func (m *Mutex) Lock() {
 			if old&mutexLocked == 0 {
 				break
 			}
-			runtime.Semacquire(&m.sema)
+			runtime_Semacquire(&m.sema)
 			awoke = true
 		}
 	}
@@ -89,7 +86,7 @@ func (m *Mutex) Unlock() {
 		// Grab the right to wake someone.
 		new = (old - 1<<mutexWaiterShift) | mutexWoken
 		if atomic.CompareAndSwapInt32(&m.state, old, new) {
-			runtime.Semrelease(&m.sema)
+			runtime_Semrelease(&m.sema)
 			return
 		}
 		old = m.state
diff --git a/libgo/go/sync/mutex_test.go b/libgo/go/sync/mutex_test.go
index a514b4ad4c0..bf78c6f609c 100644
--- a/libgo/go/sync/mutex_test.go
+++ b/libgo/go/sync/mutex_test.go
@@ -15,8 +15,8 @@ import (
 
 func HammerSemaphore(s *uint32, loops int, cdone chan bool) {
 	for i := 0; i < loops; i++ {
-		runtime.Semacquire(s)
-		runtime.Semrelease(s)
+		Runtime_Semacquire(s)
+		Runtime_Semrelease(s)
 	}
 	cdone <- true
 }
diff --git a/libgo/go/sync/runtime.go b/libgo/go/sync/runtime.go
new file mode 100644
index 00000000000..e99599c11ae
--- /dev/null
+++ b/libgo/go/sync/runtime.go
@@ -0,0 +1,18 @@
+// Copyright 2012 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package sync
+
+// defined in package runtime
+
+// Semacquire waits until *s > 0 and then atomically decrements it.
+// It is intended as a simple sleep primitive for use by the synchronization
+// library and should not be used directly.
+func runtime_Semacquire(s *uint32)
+
+// Semrelease atomically increments *s and notifies a waiting goroutine
+// if one is blocked in Semacquire.
+// It is intended as a simple wakeup primitive for use by the synchronization
+// library and should not be used directly.
+func runtime_Semrelease(s *uint32)
diff --git a/libgo/go/runtime/sema_test.go b/libgo/go/sync/runtime_sema_test.go
index d95bb1ec58f..57a8dbee783 100644
--- a/libgo/go/runtime/sema_test.go
+++ b/libgo/go/sync/runtime_sema_test.go
@@ -2,10 +2,11 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-package runtime_test
+package sync_test
 
 import (
 	"runtime"
+	. "sync"
 	"sync/atomic"
 	"testing"
 )
@@ -25,8 +26,8 @@ func BenchmarkSemaUncontended(b *testing.B) {
 			for atomic.AddInt32(&N, -1) >= 0 {
 				runtime.Gosched()
 				for g := 0; g < CallsPerSched; g++ {
-					runtime.Semrelease(&sem.sem)
-					runtime.Semacquire(&sem.sem)
+					Runtime_Semrelease(&sem.sem)
+					Runtime_Semacquire(&sem.sem)
 				}
 			}
 			c <- true
@@ -48,7 +49,7 @@ func benchmarkSema(b *testing.B, block, work bool) {
 	if block {
 		for p := 0; p < procs/2; p++ {
 			go func() {
-				runtime.Semacquire(&sem)
+				Runtime_Semacquire(&sem)
 				c2 <- true
 			}()
 		}
@@ -59,18 +60,18 @@ func benchmarkSema(b *testing.B, block, work bool) {
 			for atomic.AddInt32(&N, -1) >= 0 {
 				runtime.Gosched()
 				for g := 0; g < CallsPerSched; g++ {
-					runtime.Semrelease(&sem)
+					Runtime_Semrelease(&sem)
 					if work {
 						for i := 0; i < LocalWork; i++ {
 							foo *= 2
 							foo /= 2
 						}
 					}
-					runtime.Semacquire(&sem)
+					Runtime_Semacquire(&sem)
 				}
 			}
 			c <- foo == 42
-			runtime.Semrelease(&sem)
+			Runtime_Semrelease(&sem)
 		}()
 	}
 	if block {
diff --git a/libgo/go/sync/rwmutex.go b/libgo/go/sync/rwmutex.go
index cb1a47720b2..782a9c31968 100644
--- a/libgo/go/sync/rwmutex.go
+++ b/libgo/go/sync/rwmutex.go
@@ -4,10 +4,7 @@
 
 package sync
 
-import (
-	"runtime"
-	"sync/atomic"
-)
+import "sync/atomic"
 
 // An RWMutex is a reader/writer mutual exclusion lock.
 // The lock can be held by an arbitrary number of readers
@@ -29,7 +26,7 @@ const rwmutexMaxReaders = 1 << 30
 func (rw *RWMutex) RLock() {
 	if atomic.AddInt32(&rw.readerCount, 1) < 0 {
 		// A writer is pending, wait for it.
-		runtime.Semacquire(&rw.readerSem)
+		runtime_Semacquire(&rw.readerSem)
 	}
 }
 
@@ -42,7 +39,7 @@ func (rw *RWMutex) RUnlock() {
 		// A writer is pending.
 		if atomic.AddInt32(&rw.readerWait, -1) == 0 {
 			// The last reader unblocks the writer.
-			runtime.Semrelease(&rw.writerSem)
+			runtime_Semrelease(&rw.writerSem)
 		}
 	}
 }
@@ -60,7 +57,7 @@ func (rw *RWMutex) Lock() {
 	r := atomic.AddInt32(&rw.readerCount, -rwmutexMaxReaders) + rwmutexMaxReaders
 	// Wait for active readers.
 	if r != 0 && atomic.AddInt32(&rw.readerWait, r) != 0 {
-		runtime.Semacquire(&rw.writerSem)
+		runtime_Semacquire(&rw.writerSem)
 	}
 }
 
@@ -75,7 +72,7 @@ func (rw *RWMutex) Unlock() {
 	r := atomic.AddInt32(&rw.readerCount, rwmutexMaxReaders)
 	// Unblock blocked readers, if any.
 	for i := 0; i < int(r); i++ {
-		runtime.Semrelease(&rw.readerSem)
+		runtime_Semrelease(&rw.readerSem)
 	}
 	// Allow other writers to proceed.
 	rw.w.Unlock()
diff --git a/libgo/go/sync/waitgroup.go b/libgo/go/sync/waitgroup.go
index a4c9b7e43cd..3e7d9d3c8f4 100644
--- a/libgo/go/sync/waitgroup.go
+++ b/libgo/go/sync/waitgroup.go
@@ -4,10 +4,7 @@
 
 package sync
 
-import (
-	"runtime"
-	"sync/atomic"
-)
+import "sync/atomic"
 
 // A WaitGroup waits for a collection of goroutines to finish.
 // The main goroutine calls Add to set the number of
@@ -60,7 +57,7 @@ func (wg *WaitGroup) Add(delta int) {
 	}
 	wg.m.Lock()
 	for i := int32(0); i < wg.waiters; i++ {
-		runtime.Semrelease(wg.sema)
+		runtime_Semrelease(wg.sema)
 	}
 	wg.waiters = 0
 	wg.sema = nil
@@ -93,5 +90,5 @@ func (wg *WaitGroup) Wait() {
 	}
 	s := wg.sema
 	wg.m.Unlock()
-	runtime.Semacquire(s)
+	runtime_Semacquire(s)
 }
diff --git a/libgo/go/testing/testing.go b/libgo/go/testing/testing.go
index d5d60eae4cd..adc8c09f217 100644
--- a/libgo/go/testing/testing.go
+++ b/libgo/go/testing/testing.go
@@ -38,16 +38,25 @@
 //         }
 //     }
 //
-// The package also runs and verifies example code. Example functions
-// include an introductory comment that is compared with the standard output
-// of the function when the tests are run, as in this example of an example:
+// The package also runs and verifies example code. Example functions may
+// include a concluding comment that begins with "Output:" and is compared with
+// the standard output of the function when the tests are run, as in these
+// examples of an example:
 //
-//     // hello
 //     func ExampleHello() {
 //             fmt.Println("hello")
+//             // Output: hello
 //     }
 //
-// Example functions without comments are compiled but not executed.
+//     func ExampleSalutations() {
+//             fmt.Println("hello, and")
+//             fmt.Println("goodbye")
+//             // Output:
+//             // hello, and
+//             // goodbye
+//     }
+//
+// Example functions without output comments are compiled but not executed.
 //
 // The naming convention to declare examples for a function F, a type T and
 // method M on type T are:
diff --git a/libgo/go/text/tabwriter/example_test.go b/libgo/go/text/tabwriter/example_test.go
new file mode 100644
index 00000000000..20443cb1ffb
--- /dev/null
+++ b/libgo/go/text/tabwriter/example_test.go
@@ -0,0 +1,38 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package tabwriter_test
+
+import (
+	"fmt"
+	"os"
+	"text/tabwriter"
+)
+
+func ExampleWriter_Init() {
+	w := new(tabwriter.Writer)
+
+	// Format in tab-separated columns with a tab stop of 8.
+	w.Init(os.Stdout, 0, 8, 0, '\t', 0)
+	fmt.Fprintln(w, "a\tb\tc\td\t.")
+	fmt.Fprintln(w, "123\t12345\t1234567\t123456789\t.")
+	fmt.Fprintln(w)
+	w.Flush()
+
+	// Format right-aligned in space-separated columns of minimal width 5
+	// and at least one blank of padding (so wider column entries do not
+	// touch each other).
+	w.Init(os.Stdout, 5, 0, 1, ' ', tabwriter.AlignRight)
+	fmt.Fprintln(w, "a\tb\tc\td\t.")
+	fmt.Fprintln(w, "123\t12345\t1234567\t123456789\t.")
+	fmt.Fprintln(w)
+	w.Flush()
+
+	// output:
+	// a	b	c	d		.
+	// 123	12345	1234567	123456789	.
+	//
+	//     a     b       c         d.
+	//   123 12345 1234567 123456789.
+}
diff --git a/libgo/go/text/tabwriter/tabwriter.go b/libgo/go/text/tabwriter/tabwriter.go
index ea7c4008111..ce84600d604 100644
--- a/libgo/go/text/tabwriter/tabwriter.go
+++ b/libgo/go/text/tabwriter/tabwriter.go
@@ -169,12 +169,6 @@ const (
 //			to the tab width in the viewer displaying the result)
 //	flags		formatting control
 //
-// To format in tab-separated columns with a tab stop of 8:
-//	b.Init(w, 8, 1, 8, '\t', 0);
-//
-// To format in space-separated columns with at least 4 spaces between columns:
-//	b.Init(w, 0, 4, 8, ' ', 0);
-//
 func (b *Writer) Init(output io.Writer, minwidth, tabwidth, padding int, padchar byte, flags uint) *Writer {
 	if minwidth < 0 || tabwidth < 0 || padding < 0 {
 		panic("negative minwidth, tabwidth, or padding")
diff --git a/libgo/go/text/tabwriter/tabwriter_test.go b/libgo/go/text/tabwriter/tabwriter_test.go
index 1ffb330d432..ace53564737 100644
--- a/libgo/go/text/tabwriter/tabwriter_test.go
+++ b/libgo/go/text/tabwriter/tabwriter_test.go
@@ -2,11 +2,12 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-package tabwriter
+package tabwriter_test
 
 import (
 	"io"
 	"testing"
+	. "text/tabwriter"
 )
 
 type buffer struct {
diff --git a/libgo/go/text/template/doc.go b/libgo/go/text/template/doc.go
index 35c4c681183..ae91f4a5419 100644
--- a/libgo/go/text/template/doc.go
+++ b/libgo/go/text/template/doc.go
@@ -22,6 +22,20 @@ Actions may not span newlines, although comments can.
 
 Once constructed, a template may be executed safely in parallel.
 
+Here is a trivial example that prints "17 items are made of wool".
+
+	type Inventory struct {
+		Material string
+		Count    uint
+	}
+	sweaters := Inventory{"wool", 17}
+	tmpl, err := template.New("test").Parse("{{.Count}} items are made of {{.Material}}")
+	if err != nil { panic(err) }
+	err = tmpl.Execute(os.Stdout, sweaters)
+	if err != nil { panic(err) }
+
+More intricate examples appear below.
+
 Actions
 
 Here is the list of actions. "Arguments" and "pipelines" are evaluations of
@@ -128,6 +142,11 @@ An argument is a simple value, denoted by one of the following.
 	    .Field1.Key1.Method1.Field2.Key2.Method2
 	  Methods can also be evaluated on variables, including chaining:
 	    $x.Method1.Field
+	- The name of a niladic function-valued struct field of the data,
+	  preceded by a period, such as
+		.Function
+	  Function-valued fields behave like methods (of structs) but do not
+	  pass a receiver.
 	- The name of a niladic function, such as
 		fun
 	  The result is the value of invoking the function, fun(). The return
@@ -148,6 +167,9 @@ value (argument) or a function or method call, possibly with multiple arguments:
 		The result is the value of calling the method with the
 		arguments:
 			dot.Method(Argument1, etc.)
+	.Function [Argument...]
+		A function-valued field of a struct works like a method but does
+		not pass the receiver.
 	functionName [Argument...]
 		The result is the value of calling the function associated
 		with the name:
@@ -303,7 +325,7 @@ produce the text
 By construction, a template may reside in only one association. If it's
 necessary to have a template addressable from multiple associations, the
 template definition must be parsed multiple times to create distinct *Template
-values.
+values, or must be copied with the Clone or AddParseTree method.
 
 Parse may be called multiple times to assemble the various associated templates;
 see the ParseFiles and ParseGlob functions and methods for simple ways to parse
diff --git a/libgo/go/text/template/exec.go b/libgo/go/text/template/exec.go
index 973189a8a62..af745286c0b 100644
--- a/libgo/go/text/template/exec.go
+++ b/libgo/go/text/template/exec.go
@@ -419,10 +419,14 @@ func (s *state) evalField(dot reflect.Value, fieldName string, args []parse.Node
 		tField, ok := receiver.Type().FieldByName(fieldName)
 		if ok {
 			field := receiver.FieldByIndex(tField.Index)
-			if hasArgs {
-				s.errorf("%s is not a method but has arguments", fieldName)
-			}
 			if tField.PkgPath == "" { // field is exported
+				// If it's a function, we must call it.
+				if field.Type().Kind() == reflect.Func {
+					return s.evalCall(dot, field, fieldName, args, final)
+				}
+				if hasArgs {
+					s.errorf("%s is not a method or function but has arguments", fieldName)
+				}
 				return field
 			}
 		}
diff --git a/libgo/go/text/template/exec_test.go b/libgo/go/text/template/exec_test.go
index 9bb55e48aac..159cf5100d9 100644
--- a/libgo/go/text/template/exec_test.go
+++ b/libgo/go/text/template/exec_test.go
@@ -59,6 +59,8 @@ type T struct {
 	PI  *int
 	PSI *[]int
 	NIL *int
+	// Function (not method)
+	Func func(...string) string
 	// Template to test evaluation of templates.
 	Tmpl *Template
 }
@@ -118,6 +120,7 @@ var tVal = &T{
 	Err:               errors.New("erroozle"),
 	PI:                newInt(23),
 	PSI:               newIntSlice(21, 22, 23),
+	Func:              func(s ...string) string { return fmt.Sprint("<", strings.Join(s, "+"), ">") },
 	Tmpl:              Must(New("x").Parse("test template")), // "x" is the value of .X
 }
 
@@ -297,8 +300,13 @@ var execTests = []execTest{
 		"{{with $x := .}}{{with .SI}}{{$.GetU.TrueFalse $.True}}{{end}}{{end}}",
 		"true", tVal, true},
 
+	// Function call
+	{".Func", "-{{.Func}}-", "-<>-", tVal, true},
+	{".Func2", "-{{.Func `he` `llo`}}-", "-<he+llo>-", tVal, true},
+
 	// Pipelines.
 	{"pipeline", "-{{.Method0 | .Method2 .U16}}-", "-Method2: 16 M0-", tVal, true},
+	{"pipeline func", "-{{.Func `llo` | .Func `he` }}-", "-<he+<llo>>-", tVal, true},
 
 	// If.
 	{"if true", "{{if true}}TRUE{{end}}", "TRUE", tVal, true},
diff --git a/libgo/go/text/template/multi_test.go b/libgo/go/text/template/multi_test.go
index 274f5ef1477..f205e6be1b4 100644
--- a/libgo/go/text/template/multi_test.go
+++ b/libgo/go/text/template/multi_test.go
@@ -193,7 +193,7 @@ func TestClone(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	clone := root.Clone()
+	clone := Must(root.Clone())
 	// Add variants to both.
 	_, err = root.Parse(cloneText3)
 	if err != nil {
diff --git a/libgo/go/text/template/parse/parse.go b/libgo/go/text/template/parse/parse.go
index 4da756657d5..35194f7dfdb 100644
--- a/libgo/go/text/template/parse/parse.go
+++ b/libgo/go/text/template/parse/parse.go
@@ -2,8 +2,10 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// Package parse builds parse trees for templates.  The grammar is defined
-// in the documents for the template package.
+// Package parse builds parse trees for templates as defined by text/template
+// and html/template. Clients should use those packages to construct templates
+// rather than this one, which provides shared internal data structures not
+// intended for general use.
 package parse
 
 import (
diff --git a/libgo/go/text/template/template.go b/libgo/go/text/template/template.go
index 87e39d3af74..7494f9d8c45 100644
--- a/libgo/go/text/template/template.go
+++ b/libgo/go/text/template/template.go
@@ -69,9 +69,9 @@ func (t *Template) init() {
 // templates. The actual representation is not copied, but the name space of
 // associated templates is, so further calls to Parse in the copy will add
 // templates to the copy but not to the original. Clone can be used to prepare
-// common templates and use them with variant definitions for other templates by
-// adding the variants after the clone is made.
-func (t *Template) Clone() *Template {
+// common templates and use them with variant definitions for other templates
+// by adding the variants after the clone is made.
+func (t *Template) Clone() (*Template, error) {
 	nt := t.copy(nil)
 	nt.init()
 	nt.tmpl[t.name] = nt
@@ -89,7 +89,7 @@ func (t *Template) Clone() *Template {
 	for k, v := range t.execFuncs {
 		nt.execFuncs[k] = v
 	}
-	return nt
+	return nt, nil
 }
 
 // copy returns a shallow copy of t, with common set to the argument.
diff --git a/libgo/go/time/example_test.go b/libgo/go/time/example_test.go
index b25e64cda3e..944cc789c31 100644
--- a/libgo/go/time/example_test.go
+++ b/libgo/go/time/example_test.go
@@ -51,8 +51,8 @@ func ExampleMonth() {
 	}
 }
 
-// Go launched at 2009-11-10 15:00:00 -0800 PST
 func ExampleDate() {
 	t := time.Date(2009, time.November, 10, 23, 0, 0, 0, time.UTC)
 	fmt.Printf("Go launched at %s\n", t.Local())
+	// Output: Go launched at 2009-11-10 15:00:00 -0800 PST
 }
diff --git a/libgo/go/time/sys_plan9.go b/libgo/go/time/sys_plan9.go
index c7cfa792a29..8484729448e 100644
--- a/libgo/go/time/sys_plan9.go
+++ b/libgo/go/time/sys_plan9.go
@@ -6,7 +6,10 @@
 
 package time
 
-import "syscall"
+import (
+	"errors"
+	"syscall"
+)
 
 // for testing: whatever interrupts a sleep
 func interrupt() {
@@ -38,3 +41,36 @@ func readFile(name string) ([]byte, error) {
 	}
 	return ret, err
 }
+
+func open(name string) (uintptr, error) {
+	fd, err := syscall.Open(name, syscall.O_RDONLY)
+	if err != nil {
+		return 0, err
+	}
+	return uintptr(fd), nil
+}
+
+func closefd(fd uintptr) {
+	syscall.Close(int(fd))
+}
+
+func preadn(fd uintptr, buf []byte, off int) error {
+	whence := 0
+	if off < 0 {
+		whence = 2
+	}
+	if _, err := syscall.Seek(int(fd), int64(off), whence); err != nil {
+		return err
+	}
+	for len(buf) > 0 {
+		m, err := syscall.Read(int(fd), buf)
+		if m <= 0 {
+			if err == nil {
+				return errors.New("short read")
+			}
+			return err
+		}
+		buf = buf[m:]
+	}
+	return nil
+}
diff --git a/libgo/go/time/sys_unix.go b/libgo/go/time/sys_unix.go
index 56a7414e0ce..7f69b492c9f 100644
--- a/libgo/go/time/sys_unix.go
+++ b/libgo/go/time/sys_unix.go
@@ -6,7 +6,10 @@
 
 package time
 
-import "syscall"
+import (
+	"errors"
+	"syscall"
+)
 
 // for testing: whatever interrupts a sleep
 func interrupt() {
@@ -38,3 +41,36 @@ func readFile(name string) ([]byte, error) {
 	}
 	return ret, err
 }
+
+func open(name string) (uintptr, error) {
+	fd, err := syscall.Open(name, syscall.O_RDONLY, 0)
+	if err != nil {
+		return 0, err
+	}
+	return uintptr(fd), nil
+}
+
+func closefd(fd uintptr) {
+	syscall.Close(int(fd))
+}
+
+func preadn(fd uintptr, buf []byte, off int) error {
+	whence := 0
+	if off < 0 {
+		whence = 2
+	}
+	if _, err := syscall.Seek(int(fd), int64(off), whence); err != nil {
+		return err
+	}
+	for len(buf) > 0 {
+		m, err := syscall.Read(int(fd), buf)
+		if m <= 0 {
+			if err == nil {
+				return errors.New("short read")
+			}
+			return err
+		}
+		buf = buf[m:]
+	}
+	return nil
+}
diff --git a/libgo/go/time/sys_windows.go b/libgo/go/time/sys_windows.go
index 8c7242f4275..de63b4bf4bb 100644
--- a/libgo/go/time/sys_windows.go
+++ b/libgo/go/time/sys_windows.go
@@ -4,6 +4,70 @@
 
 package time
 
+import (
+	"errors"
+	"syscall"
+)
+
 // for testing: whatever interrupts a sleep
 func interrupt() {
 }
+
+// readFile reads and returns the content of the named file.
+// It is a trivial implementation of ioutil.ReadFile, reimplemented
+// here to avoid depending on io/ioutil or os.
+func readFile(name string) ([]byte, error) {
+	f, err := syscall.Open(name, syscall.O_RDONLY, 0)
+	if err != nil {
+		return nil, err
+	}
+	defer syscall.Close(f)
+	var (
+		buf [4096]byte
+		ret []byte
+		n   int
+	)
+	for {
+		n, err = syscall.Read(f, buf[:])
+		if n > 0 {
+			ret = append(ret, buf[:n]...)
+		}
+		if n == 0 || err != nil {
+			break
+		}
+	}
+	return ret, err
+}
+
+func open(name string) (uintptr, error) {
+	fd, err := syscall.Open(name, syscall.O_RDONLY, 0)
+	if err != nil {
+		return 0, err
+	}
+	return uintptr(fd), nil
+}
+
+func closefd(fd uintptr) {
+	syscall.Close(syscall.Handle(fd))
+}
+
+func preadn(fd uintptr, buf []byte, off int) error {
+	whence := 0
+	if off < 0 {
+		whence = 2
+	}
+	if _, err := syscall.Seek(syscall.Handle(fd), int64(off), whence); err != nil {
+		return err
+	}
+	for len(buf) > 0 {
+		m, err := syscall.Read(syscall.Handle(fd), buf)
+		if m <= 0 {
+			if err == nil {
+				return errors.New("short read")
+			}
+			return err
+		}
+		buf = buf[m:]
+	}
+	return nil
+}
diff --git a/libgo/go/time/tick_test.go b/libgo/go/time/tick_test.go
index 0c1c4d67ab0..914f02c861c 100644
--- a/libgo/go/time/tick_test.go
+++ b/libgo/go/time/tick_test.go
@@ -12,9 +12,6 @@ import (
 func TestTicker(t *testing.T) {
 	const Count = 10
 	Delta := 100 * Millisecond
-	if testing.Short() {
-		Delta = 10 * Millisecond
-	}
 	ticker := NewTicker(Delta)
 	t0 := Now()
 	for i := 0; i < Count; i++ {
diff --git a/libgo/go/time/zoneinfo.go b/libgo/go/time/zoneinfo.go
index aca56e746af..3c57744043e 100644
--- a/libgo/go/time/zoneinfo.go
+++ b/libgo/go/time/zoneinfo.go
@@ -4,7 +4,10 @@
 
 package time
 
-import "sync"
+import (
+	"sync"
+	"syscall"
+)
 
 // A Location maps time instants to the zone in use at that time.
 // Typically, the Location represents the collection of time offsets
@@ -168,10 +171,7 @@ func (l *Location) lookupOffset(offset int) (name string, isDST bool, ok bool) {
 // NOTE(rsc): Eventually we will need to accept the POSIX TZ environment
 // syntax too, but I don't feel like implementing it today.
 
-// NOTE(rsc): Using the IANA names below means ensuring we have access
-// to the database.  Probably we will ship the files in $GOROOT/lib/zoneinfo/
-// and only look there if there are no system files available (such as on Windows).
-// The files total 200 kB.
+var zoneinfo, _ = syscall.Getenv("ZONEINFO")
 
 // LoadLocation returns the Location with the given name.
 //
@@ -180,6 +180,13 @@ func (l *Location) lookupOffset(offset int) (name string, isDST bool, ok bool) {
 //
 // Otherwise, the name is taken to be a location name corresponding to a file
 // in the IANA Time Zone database, such as "America/New_York".
+//
+// The time zone database needed by LoadLocation may not be
+// present on all systems, especially non-Unix systems.
+// LoadLocation looks in the directory or uncompressed zip file
+// named by the ZONEINFO environment variable, if any, then looks in
+// known installation locations on Unix systems,
+// and finally looks in $GOROOT/lib/time/zoneinfo.zip.
 func LoadLocation(name string) (*Location, error) {
 	if name == "" || name == "UTC" {
 		return UTC, nil
@@ -187,5 +194,11 @@ func LoadLocation(name string) (*Location, error) {
 	if name == "Local" {
 		return Local, nil
 	}
+	if zoneinfo != "" {
+		if z, err := loadZoneFile(zoneinfo, name); err == nil {
+			z.name = name
+			return z, nil
+		}
+	}
 	return loadLocation(name)
 }
diff --git a/libgo/go/time/zoneinfo_plan9.go b/libgo/go/time/zoneinfo_plan9.go
index 9c052d42cd3..6855238dc84 100644
--- a/libgo/go/time/zoneinfo_plan9.go
+++ b/libgo/go/time/zoneinfo_plan9.go
@@ -8,11 +8,10 @@ package time
 
 import (
 	"errors"
+	"runtime"
 	"syscall"
 )
 
-var badData = errors.New("malformed time zone information")
-
 func isSpace(r rune) bool {
 	return r == ' ' || r == '\t' || r == '\n'
 }
@@ -51,7 +50,7 @@ func fields(s string) []string {
 	return a
 }
 
-func loadZoneData(s string) (l *Location, err error) {
+func loadZoneDataPlan9(s string) (l *Location, err error) {
 	f := fields(s)
 	if len(f) < 4 {
 		if len(f) == 2 && f[0] == "GMT" {
@@ -112,33 +111,32 @@ func loadZoneData(s string) (l *Location, err error) {
 	return l, nil
 }
 
-func loadZoneFile(name string) (*Location, error) {
+func loadZoneFilePlan9(name string) (*Location, error) {
 	b, err := readFile(name)
 	if err != nil {
 		return nil, err
 	}
-	return loadZoneData(string(b))
+	return loadZoneDataPlan9(string(b))
 }
 
 func initTestingZone() {
-	if z, err := loadZoneFile("/adm/timezone/US_Pacific"); err == nil {
-		localLoc = *z
-		return
+	z, err := loadLocation("America/Los_Angeles")
+	if err != nil {
+		panic("cannot load America/Los_Angeles for testing: " + err.Error())
 	}
-
-	// Fall back to UTC.
-	localLoc.name = "UTC"
+	z.name = "Local"
+	localLoc = *z
 }
 
 func initLocal() {
 	t, ok := syscall.Getenv("timezone")
 	if ok {
-		if z, err := loadZoneData(t); err == nil {
+		if z, err := loadZoneDataPlan9(t); err == nil {
 			localLoc = *z
 			return
 		}
 	} else {
-		if z, err := loadZoneFile("/adm/timezone/local"); err == nil {
+		if z, err := loadZoneFilePlan9("/adm/timezone/local"); err == nil {
 			localLoc = *z
 			localLoc.name = "Local"
 			return
@@ -150,7 +148,8 @@ func initLocal() {
 }
 
 func loadLocation(name string) (*Location, error) {
-	if z, err := loadZoneFile("/adm/timezone/" + name); err == nil {
+	if z, err := loadZoneFile(runtime.GOROOT()+"/lib/time/zoneinfo.zip", name); err == nil {
+		z.name = name
 		return z, nil
 	}
 	return nil, errors.New("unknown time zone " + name)
diff --git a/libgo/go/time/zoneinfo_read.go b/libgo/go/time/zoneinfo_read.go
new file mode 100644
index 00000000000..ebb4205a98f
--- /dev/null
+++ b/libgo/go/time/zoneinfo_read.go
@@ -0,0 +1,341 @@
+// Copyright 2009 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.
+
+// Parse "zoneinfo" time zone file.
+// This is a fairly standard file format used on OS X, Linux, BSD, Sun, and others.
+// See tzfile(5), http://en.wikipedia.org/wiki/Zoneinfo,
+// and ftp://munnari.oz.au/pub/oldtz/
+
+package time
+
+import "errors"
+
+const (
+	headerSize = 4 + 16 + 4*7
+)
+
+// Simple I/O interface to binary blob of data.
+type data struct {
+	p     []byte
+	error bool
+}
+
+func (d *data) read(n int) []byte {
+	if len(d.p) < n {
+		d.p = nil
+		d.error = true
+		return nil
+	}
+	p := d.p[0:n]
+	d.p = d.p[n:]
+	return p
+}
+
+func (d *data) big4() (n uint32, ok bool) {
+	p := d.read(4)
+	if len(p) < 4 {
+		d.error = true
+		return 0, false
+	}
+	return uint32(p[0])<<24 | uint32(p[1])<<16 | uint32(p[2])<<8 | uint32(p[3]), true
+}
+
+func (d *data) byte() (n byte, ok bool) {
+	p := d.read(1)
+	if len(p) < 1 {
+		d.error = true
+		return 0, false
+	}
+	return p[0], true
+}
+
+// Make a string by stopping at the first NUL
+func byteString(p []byte) string {
+	for i := 0; i < len(p); i++ {
+		if p[i] == 0 {
+			return string(p[0:i])
+		}
+	}
+	return string(p)
+}
+
+var badData = errors.New("malformed time zone information")
+
+func loadZoneData(bytes []byte) (l *Location, err error) {
+	d := data{bytes, false}
+
+	// 4-byte magic "TZif"
+	if magic := d.read(4); string(magic) != "TZif" {
+		return nil, badData
+	}
+
+	// 1-byte version, then 15 bytes of padding
+	var p []byte
+	if p = d.read(16); len(p) != 16 || p[0] != 0 && p[0] != '2' {
+		return nil, badData
+	}
+
+	// six big-endian 32-bit integers:
+	//	number of UTC/local indicators
+	//	number of standard/wall indicators
+	//	number of leap seconds
+	//	number of transition times
+	//	number of local time zones
+	//	number of characters of time zone abbrev strings
+	const (
+		NUTCLocal = iota
+		NStdWall
+		NLeap
+		NTime
+		NZone
+		NChar
+	)
+	var n [6]int
+	for i := 0; i < 6; i++ {
+		nn, ok := d.big4()
+		if !ok {
+			return nil, badData
+		}
+		n[i] = int(nn)
+	}
+
+	// Transition times.
+	txtimes := data{d.read(n[NTime] * 4), false}
+
+	// Time zone indices for transition times.
+	txzones := d.read(n[NTime])
+
+	// Zone info structures
+	zonedata := data{d.read(n[NZone] * 6), false}
+
+	// Time zone abbreviations.
+	abbrev := d.read(n[NChar])
+
+	// Leap-second time pairs
+	d.read(n[NLeap] * 8)
+
+	// Whether tx times associated with local time types
+	// are specified as standard time or wall time.
+	isstd := d.read(n[NStdWall])
+
+	// Whether tx times associated with local time types
+	// are specified as UTC or local time.
+	isutc := d.read(n[NUTCLocal])
+
+	if d.error { // ran out of data
+		return nil, badData
+	}
+
+	// If version == 2, the entire file repeats, this time using
+	// 8-byte ints for txtimes and leap seconds.
+	// We won't need those until 2106.
+
+	// Now we can build up a useful data structure.
+	// First the zone information.
+	//	utcoff[4] isdst[1] nameindex[1]
+	zone := make([]zone, n[NZone])
+	for i := range zone {
+		var ok bool
+		var n uint32
+		if n, ok = zonedata.big4(); !ok {
+			return nil, badData
+		}
+		zone[i].offset = int(n)
+		var b byte
+		if b, ok = zonedata.byte(); !ok {
+			return nil, badData
+		}
+		zone[i].isDST = b != 0
+		if b, ok = zonedata.byte(); !ok || int(b) >= len(abbrev) {
+			return nil, badData
+		}
+		zone[i].name = byteString(abbrev[b:])
+	}
+
+	// Now the transition time info.
+	tx := make([]zoneTrans, n[NTime])
+	for i := range tx {
+		var ok bool
+		var n uint32
+		if n, ok = txtimes.big4(); !ok {
+			return nil, badData
+		}
+		tx[i].when = int64(int32(n))
+		if int(txzones[i]) >= len(zone) {
+			return nil, badData
+		}
+		tx[i].index = txzones[i]
+		if i < len(isstd) {
+			tx[i].isstd = isstd[i] != 0
+		}
+		if i < len(isutc) {
+			tx[i].isutc = isutc[i] != 0
+		}
+	}
+
+	// Commited to succeed.
+	l = &Location{zone: zone, tx: tx}
+
+	// Fill in the cache with information about right now,
+	// since that will be the most common lookup.
+	sec, _ := now()
+	for i := range tx {
+		if tx[i].when <= sec && (i+1 == len(tx) || sec < tx[i+1].when) {
+			l.cacheStart = tx[i].when
+			l.cacheEnd = 1<<63 - 1
+			if i+1 < len(tx) {
+				l.cacheEnd = tx[i+1].when
+			}
+			l.cacheZone = &l.zone[tx[i].index]
+		}
+	}
+
+	return l, nil
+}
+
+func loadZoneFile(dir, name string) (l *Location, err error) {
+	if len(dir) > 4 && dir[len(dir)-4:] == ".zip" {
+		return loadZoneZip(dir, name)
+	}
+	if dir != "" {
+		name = dir + "/" + name
+	}
+	buf, err := readFile(name)
+	if err != nil {
+		return
+	}
+	return loadZoneData(buf)
+}
+
+// There are 500+ zoneinfo files.  Rather than distribute them all
+// individually, we ship them in an uncompressed zip file.
+// Used this way, the zip file format serves as a commonly readable
+// container for the individual small files.  We choose zip over tar
+// because zip files have a contiguous table of contents, making
+// individual file lookups faster, and because the per-file overhead
+// in a zip file is considerably less than tar's 512 bytes.
+
+// get4 returns the little-endian 32-bit value in b.
+func get4(b []byte) int {
+	if len(b) < 4 {
+		return 0
+	}
+	return int(b[0]) | int(b[1])<<8 | int(b[2])<<16 | int(b[3])<<24
+}
+
+// get2 returns the little-endian 16-bit value in b.
+func get2(b []byte) int {
+	if len(b) < 2 {
+		return 0
+	}
+	return int(b[0]) | int(b[1])<<8
+}
+
+func loadZoneZip(zipfile, name string) (l *Location, err error) {
+	fd, err := open(zipfile)
+	if err != nil {
+		return nil, errors.New("open " + zipfile + ": " + err.Error())
+	}
+	defer closefd(fd)
+
+	const (
+		zecheader = 0x06054b50
+		zcheader  = 0x02014b50
+		ztailsize = 22
+
+		zheadersize = 30
+		zheader     = 0x04034b50
+	)
+
+	buf := make([]byte, ztailsize)
+	if err := preadn(fd, buf, -ztailsize); err != nil || get4(buf) != zecheader {
+		return nil, errors.New("corrupt zip file " + zipfile)
+	}
+	n := get2(buf[10:])
+	size := get4(buf[12:])
+	off := get4(buf[16:])
+
+	buf = make([]byte, size)
+	if err := preadn(fd, buf, off); err != nil {
+		return nil, errors.New("corrupt zip file " + zipfile)
+	}
+
+	for i := 0; i < n; i++ {
+		// zip entry layout:
+		//	0	magic[4]
+		//	4	madevers[1]
+		//	5	madeos[1]
+		//	6	extvers[1]
+		//	7	extos[1]
+		//	8	flags[2]
+		//	10	meth[2]
+		//	12	modtime[2]
+		//	14	moddate[2]
+		//	16	crc[4]
+		//	20	csize[4]
+		//	24	uncsize[4]
+		//	28	namelen[2]
+		//	30	xlen[2]
+		//	32	fclen[2]
+		//	34	disknum[2]
+		//	36	iattr[2]
+		//	38	eattr[4]
+		//	42	off[4]
+		//	46	name[namelen]
+		//	46+namelen+xlen+fclen - next header
+		//		
+		if get4(buf) != zcheader {
+			break
+		}
+		meth := get2(buf[10:])
+		size := get4(buf[24:])
+		namelen := get2(buf[28:])
+		xlen := get2(buf[30:])
+		fclen := get2(buf[32:])
+		off := get4(buf[42:])
+		zname := buf[46 : 46+namelen]
+		buf = buf[46+namelen+xlen+fclen:]
+		if string(zname) != name {
+			continue
+		}
+		if meth != 0 {
+			return nil, errors.New("unsupported compression for " + name + " in " + zipfile)
+		}
+
+		// zip per-file header layout:
+		//	0	magic[4]
+		//	4	extvers[1]
+		//	5	extos[1]
+		//	6	flags[2]
+		//	8	meth[2]
+		//	10	modtime[2]
+		//	12	moddate[2]
+		//	14	crc[4]
+		//	18	csize[4]
+		//	22	uncsize[4]
+		//	26	namelen[2]
+		//	28	xlen[2]
+		//	30	name[namelen]
+		//	30+namelen+xlen - file data
+		//
+		buf = make([]byte, zheadersize+namelen)
+		if err := preadn(fd, buf, off); err != nil ||
+			get4(buf) != zheader ||
+			get2(buf[8:]) != meth ||
+			get2(buf[26:]) != namelen ||
+			string(buf[30:30+namelen]) != name {
+			return nil, errors.New("corrupt zip file " + zipfile)
+		}
+		xlen = get2(buf[28:])
+
+		buf = make([]byte, size)
+		if err := preadn(fd, buf, off+30+namelen+xlen); err != nil {
+			return nil, errors.New("corrupt zip file " + zipfile)
+		}
+
+		return loadZoneData(buf)
+	}
+
+	return nil, errors.New("cannot find " + name + " in zip file " + zipfile)
+}
diff --git a/libgo/go/time/zoneinfo_unix.go b/libgo/go/time/zoneinfo_unix.go
index 540b653c57d..1bf1f11e24f 100644
--- a/libgo/go/time/zoneinfo_unix.go
+++ b/libgo/go/time/zoneinfo_unix.go
@@ -13,200 +13,10 @@ package time
 
 import (
 	"errors"
+	"runtime"
 	"syscall"
 )
 
-const (
-	headerSize = 4 + 16 + 4*7
-)
-
-// Simple I/O interface to binary blob of data.
-type data struct {
-	p     []byte
-	error bool
-}
-
-func (d *data) read(n int) []byte {
-	if len(d.p) < n {
-		d.p = nil
-		d.error = true
-		return nil
-	}
-	p := d.p[0:n]
-	d.p = d.p[n:]
-	return p
-}
-
-func (d *data) big4() (n uint32, ok bool) {
-	p := d.read(4)
-	if len(p) < 4 {
-		d.error = true
-		return 0, false
-	}
-	return uint32(p[0])<<24 | uint32(p[1])<<16 | uint32(p[2])<<8 | uint32(p[3]), true
-}
-
-func (d *data) byte() (n byte, ok bool) {
-	p := d.read(1)
-	if len(p) < 1 {
-		d.error = true
-		return 0, false
-	}
-	return p[0], true
-}
-
-// Make a string by stopping at the first NUL
-func byteString(p []byte) string {
-	for i := 0; i < len(p); i++ {
-		if p[i] == 0 {
-			return string(p[0:i])
-		}
-	}
-	return string(p)
-}
-
-var badData = errors.New("malformed time zone information")
-
-func loadZoneData(bytes []byte) (l *Location, err error) {
-	d := data{bytes, false}
-
-	// 4-byte magic "TZif"
-	if magic := d.read(4); string(magic) != "TZif" {
-		return nil, badData
-	}
-
-	// 1-byte version, then 15 bytes of padding
-	var p []byte
-	if p = d.read(16); len(p) != 16 || p[0] != 0 && p[0] != '2' {
-		return nil, badData
-	}
-
-	// six big-endian 32-bit integers:
-	//	number of UTC/local indicators
-	//	number of standard/wall indicators
-	//	number of leap seconds
-	//	number of transition times
-	//	number of local time zones
-	//	number of characters of time zone abbrev strings
-	const (
-		NUTCLocal = iota
-		NStdWall
-		NLeap
-		NTime
-		NZone
-		NChar
-	)
-	var n [6]int
-	for i := 0; i < 6; i++ {
-		nn, ok := d.big4()
-		if !ok {
-			return nil, badData
-		}
-		n[i] = int(nn)
-	}
-
-	// Transition times.
-	txtimes := data{d.read(n[NTime] * 4), false}
-
-	// Time zone indices for transition times.
-	txzones := d.read(n[NTime])
-
-	// Zone info structures
-	zonedata := data{d.read(n[NZone] * 6), false}
-
-	// Time zone abbreviations.
-	abbrev := d.read(n[NChar])
-
-	// Leap-second time pairs
-	d.read(n[NLeap] * 8)
-
-	// Whether tx times associated with local time types
-	// are specified as standard time or wall time.
-	isstd := d.read(n[NStdWall])
-
-	// Whether tx times associated with local time types
-	// are specified as UTC or local time.
-	isutc := d.read(n[NUTCLocal])
-
-	if d.error { // ran out of data
-		return nil, badData
-	}
-
-	// If version == 2, the entire file repeats, this time using
-	// 8-byte ints for txtimes and leap seconds.
-	// We won't need those until 2106.
-
-	// Now we can build up a useful data structure.
-	// First the zone information.
-	//	utcoff[4] isdst[1] nameindex[1]
-	zone := make([]zone, n[NZone])
-	for i := range zone {
-		var ok bool
-		var n uint32
-		if n, ok = zonedata.big4(); !ok {
-			return nil, badData
-		}
-		zone[i].offset = int(n)
-		var b byte
-		if b, ok = zonedata.byte(); !ok {
-			return nil, badData
-		}
-		zone[i].isDST = b != 0
-		if b, ok = zonedata.byte(); !ok || int(b) >= len(abbrev) {
-			return nil, badData
-		}
-		zone[i].name = byteString(abbrev[b:])
-	}
-
-	// Now the transition time info.
-	tx := make([]zoneTrans, n[NTime])
-	for i := range tx {
-		var ok bool
-		var n uint32
-		if n, ok = txtimes.big4(); !ok {
-			return nil, badData
-		}
-		tx[i].when = int64(int32(n))
-		if int(txzones[i]) >= len(zone) {
-			return nil, badData
-		}
-		tx[i].index = txzones[i]
-		if i < len(isstd) {
-			tx[i].isstd = isstd[i] != 0
-		}
-		if i < len(isutc) {
-			tx[i].isutc = isutc[i] != 0
-		}
-	}
-
-	// Commited to succeed.
-	l = &Location{zone: zone, tx: tx}
-
-	// Fill in the cache with information about right now,
-	// since that will be the most common lookup.
-	sec, _ := now()
-	for i := range tx {
-		if tx[i].when <= sec && (i+1 == len(tx) || sec < tx[i+1].when) {
-			l.cacheStart = tx[i].when
-			l.cacheEnd = 1<<63 - 1
-			if i+1 < len(tx) {
-				l.cacheEnd = tx[i+1].when
-			}
-			l.cacheZone = &l.zone[tx[i].index]
-		}
-	}
-
-	return l, nil
-}
-
-func loadZoneFile(name string) (l *Location, err error) {
-	buf, err := readFile(name)
-	if err != nil {
-		return
-	}
-	return loadZoneData(buf)
-}
-
 func initTestingZone() {
 	syscall.Setenv("TZ", "America/Los_Angeles")
 	initLocal()
@@ -218,6 +28,7 @@ var zoneDirs = []string{
 	"/usr/share/zoneinfo/",
 	"/usr/share/lib/zoneinfo/",
 	"/usr/lib/locale/TZ/",
+	runtime.GOROOT() + "/lib/time/zoneinfo/",
 }
 
 func initLocal() {
@@ -229,7 +40,7 @@ func initLocal() {
 	tz, ok := syscall.Getenv("TZ")
 	switch {
 	case !ok:
-		z, err := loadZoneFile("/etc/localtime")
+		z, err := loadZoneFile("", "/etc/localtime")
 		if err == nil {
 			localLoc = *z
 			localLoc.name = "Local"
@@ -248,7 +59,7 @@ func initLocal() {
 
 func loadLocation(name string) (*Location, error) {
 	for _, zoneDir := range zoneDirs {
-		if z, err := loadZoneFile(zoneDir + name); err == nil {
+		if z, err := loadZoneFile(zoneDir, name); err == nil {
 			z.name = name
 			return z, nil
 		}
diff --git a/libgo/go/time/zoneinfo_windows.go b/libgo/go/time/zoneinfo_windows.go
index beef4de92b0..754e392deca 100644
--- a/libgo/go/time/zoneinfo_windows.go
+++ b/libgo/go/time/zoneinfo_windows.go
@@ -6,6 +6,7 @@ package time
 
 import (
 	"errors"
+	"runtime"
 	"syscall"
 )
 
@@ -151,7 +152,10 @@ func initLocal() {
 	initLocalFromTZI(&i)
 }
 
-// TODO(rsc): Implement.
 func loadLocation(name string) (*Location, error) {
+	if z, err := loadZoneFile(runtime.GOROOT()+`\lib\time\zoneinfo.zip`, name); err == nil {
+		z.name = name
+		return z, nil
+	}
 	return nil, errors.New("unknown time zone " + name)
 }
diff --git a/libgo/runtime/malloc.goc b/libgo/runtime/malloc.goc
index 8b48c866346..23641e8298f 100644
--- a/libgo/runtime/malloc.goc
+++ b/libgo/runtime/malloc.goc
@@ -19,6 +19,7 @@ package runtime
 #include "go-type.h"
 
 MHeap runtime_mheap;
+
 extern MStats mstats;	// defined in extern.go
 
 extern volatile int32 runtime_MemProfileRate
@@ -429,18 +430,6 @@ func new(typ *Type) (ret *uint8) {
 	ret = runtime_mallocgc(typ->__size, flag, 1, 1);
 }
 
-func Alloc(n uintptr) (p *byte) {
-	p = runtime_malloc(n);
-}
-
-func Free(p *byte) {
-	runtime_free(p);
-}
-
-func Lookup(p *byte) (base *byte, size uintptr) {
-	runtime_mlookup(p, &base, &size, nil);
-}
-
 func GC() {
 	runtime_gc(1);
 }
diff --git a/libgo/runtime/malloc.h b/libgo/runtime/malloc.h
index c1cf02c6deb..4cb07477f15 100644
--- a/libgo/runtime/malloc.h
+++ b/libgo/runtime/malloc.h
@@ -205,6 +205,7 @@ struct MStats
 	uint64	heap_sys;	// bytes obtained from system
 	uint64	heap_idle;	// bytes in idle spans
 	uint64	heap_inuse;	// bytes in non-idle spans
+	uint64	heap_released;	// bytes released to the OS
 	uint64	heap_objects;	// total number of allocated objects
 
 	// Statistics about allocation of low-level fixed-size structures.
@@ -220,6 +221,7 @@ struct MStats
 	// Statistics about garbage collector.
 	// Protected by stopping the world during GC.
 	uint64	next_gc;	// next GC (in heap_alloc time)
+	uint64  last_gc;	// last GC (in absolute time)
 	uint64	pause_total_ns;
 	uint64	pause_ns[256];
 	uint32	numgc;
@@ -304,14 +306,16 @@ struct MSpan
 {
 	MSpan	*next;		// in a span linked list
 	MSpan	*prev;		// in a span linked list
-	MSpan	*allnext;		// in the list of all spans
+	MSpan	*allnext;	// in the list of all spans
 	PageID	start;		// starting page number
 	uintptr	npages;		// number of pages in span
 	MLink	*freelist;	// list of free objects
 	uint32	ref;		// number of allocated objects in this span
 	uint32	sizeclass;	// size class
 	uint32	state;		// MSpanInUse etc
-	byte	*limit;	// end of data in span
+	int64   unusedsince;	// First time spotted by GC in MSpanFree state
+	uintptr npreleased;	// number of pages released to the OS
+	byte	*limit;		// end of data in span
 };
 
 void	runtime_MSpan_Init(MSpan *span, PageID start, uintptr npages);
@@ -381,6 +385,7 @@ MSpan*	runtime_MHeap_LookupMaybe(MHeap *h, void *v);
 void	runtime_MGetSizeClassInfo(int32 sizeclass, uintptr *size, int32 *npages, int32 *nobj);
 void*	runtime_MHeap_SysAlloc(MHeap *h, uintptr n);
 void	runtime_MHeap_MapBits(MHeap *h);
+void	runtime_MHeap_Scavenger(void*);
 
 void*	runtime_mallocgc(uintptr size, uint32 flag, int32 dogc, int32 zeroed);
 int32	runtime_mlookup(void *v, byte **base, uintptr *size, MSpan **s);
@@ -406,19 +411,11 @@ enum
 
 void	runtime_MProf_Malloc(void*, uintptr);
 void	runtime_MProf_Free(void*, uintptr);
+void	runtime_MProf_GC(void);
 void	runtime_MProf_Mark(void (*scan)(byte *, int64));
 int32	runtime_helpgc(bool*);
 void	runtime_gchelper(void);
 
-// Malloc profiling settings.
-// Must match definition in extern.go.
-enum {
-	MProf_None = 0,
-	MProf_Sample = 1,
-	MProf_All = 2,
-};
-extern int32 runtime_malloc_profile;
-
 struct __go_func_type;
 bool	runtime_getfinalizer(void *p, bool del, void (**fn)(void*), const struct __go_func_type **ft);
 void	runtime_walkfintab(void (*fn)(void*), void (*scan)(byte *, int64));
diff --git a/libgo/runtime/mgc0.c b/libgo/runtime/mgc0.c
index 73c399df239..d852946cdbb 100644
--- a/libgo/runtime/mgc0.c
+++ b/libgo/runtime/mgc0.c
@@ -61,6 +61,21 @@ enum {
 
 #define bitMask (bitBlockBoundary | bitAllocated | bitMarked | bitSpecial)
 
+// Holding worldsema grants an M the right to try to stop the world.
+// The procedure is:
+//
+//	runtime_semacquire(&runtime_worldsema);
+//	m->gcing = 1;
+//	runtime_stoptheworld();
+//
+//	... do stuff ...
+//
+//	m->gcing = 0;
+//	runtime_semrelease(&runtime_worldsema);
+//	runtime_starttheworld();
+//
+uint32 runtime_worldsema = 1;
+
 // TODO: Make these per-M.
 static uint64 nhandoff;
 
@@ -92,7 +107,6 @@ struct FinBlock
 	Finalizer fin[1];
 };
 
-
 static G *fing;
 static FinBlock *finq; // list of finalizers that are to be executed
 static FinBlock *finc; // cache of free blocks
@@ -778,9 +792,11 @@ sweep(void)
 	byte *p;
 	MCache *c;
 	byte *arena_start;
+	int64 now;
 
 	m = runtime_m();
 	arena_start = runtime_mheap.arena_start;
+	now = runtime_nanotime();
 
 	for(;;) {
 		s = work.spans;
@@ -789,6 +805,11 @@ sweep(void)
 		if(!runtime_casp(&work.spans, s, s->allnext))
 			continue;
 
+		// Stamp newly unused spans. The scavenger will use that
+		// info to potentially give back some pages to the OS.
+		if(s->state == MSpanFree && s->unusedsince == 0)
+			s->unusedsince = now;
+
 		if(s->state != MSpanInUse)
 			continue;
 
@@ -875,11 +896,6 @@ runtime_gchelper(void)
 		runtime_notewakeup(&work.alldone);
 }
 
-// Semaphore, not Lock, so that the goroutine
-// reschedules when there is contention rather
-// than spinning.
-static uint32 gcsema = 1;
-
 // Initialized from $GOGC.  GOGC=off means no gc.
 //
 // Next gc is after we've allocated an extra amount of
@@ -968,9 +984,9 @@ runtime_gc(int32 force)
 	if(gcpercent < 0)
 		return;
 
-	runtime_semacquire(&gcsema);
+	runtime_semacquire(&runtime_worldsema);
 	if(!force && mstats.heap_alloc < mstats.next_gc) {
-		runtime_semrelease(&gcsema);
+		runtime_semrelease(&runtime_worldsema);
 		return;
 	}
 
@@ -1032,6 +1048,7 @@ runtime_gc(int32 force)
 	obj1 = mstats.nmalloc - mstats.nfree;
 
 	t3 = runtime_nanotime();
+	mstats.last_gc = t3;
 	mstats.pause_ns[mstats.numgc%nelem(mstats.pause_ns)] = t3 - t0;
 	mstats.pause_total_ns += t3 - t0;
 	mstats.numgc++;
@@ -1045,8 +1062,9 @@ runtime_gc(int32 force)
 			(unsigned long long) mstats.nmalloc, (unsigned long long)mstats.nfree,
 			(unsigned long long) nhandoff);
 	}
-
-	runtime_semrelease(&gcsema);
+	
+	runtime_MProf_GC();
+	runtime_semrelease(&runtime_worldsema);
 
 	// If we could have used another helper proc, start one now,
 	// in the hope that it will be available next time.
@@ -1073,18 +1091,18 @@ runtime_ReadMemStats(MStats *stats)
 {
 	M *m;
 
-	// Have to acquire gcsema to stop the world,
+	// Have to acquire worldsema to stop the world,
 	// because stoptheworld can only be used by
 	// one goroutine at a time, and there might be
 	// a pending garbage collection already calling it.
-	runtime_semacquire(&gcsema);
+	runtime_semacquire(&runtime_worldsema);
 	m = runtime_m();
 	m->gcing = 1;
 	runtime_stoptheworld();
 	cachestats();
 	*stats = mstats;
 	m->gcing = 0;
-	runtime_semrelease(&gcsema);
+	runtime_semrelease(&runtime_worldsema);
 	runtime_starttheworld(false);
 }
 
diff --git a/libgo/runtime/mheap.c b/libgo/runtime/mheap.c
index 5a5a1e71a12..79359d9dfca 100644
--- a/libgo/runtime/mheap.c
+++ b/libgo/runtime/mheap.c
@@ -103,6 +103,8 @@ HaveSpan:
 	runtime_MSpanList_Remove(s);
 	s->state = MSpanInUse;
 	mstats.heap_idle -= s->npages<<PageShift;
+	mstats.heap_released -= s->npreleased<<PageShift;
+	s->npreleased = 0;
 
 	if(s->npages > npage) {
 		// Trim extra and put it back in the heap.
@@ -280,6 +282,8 @@ MHeap_FreeLocked(MHeap *h, MSpan *s)
 	}
 	mstats.heap_idle += s->npages<<PageShift;
 	s->state = MSpanFree;
+	s->unusedsince = 0;
+	s->npreleased = 0;
 	runtime_MSpanList_Remove(s);
 	sp = (uintptr*)(s->start<<PageShift);
 
@@ -292,6 +296,7 @@ MHeap_FreeLocked(MHeap *h, MSpan *s)
 		*tp |= *sp;	// propagate "needs zeroing" mark
 		s->start = t->start;
 		s->npages += t->npages;
+		s->npreleased = t->npreleased; // absorb released pages
 		p -= t->npages;
 		h->map[p] = s;
 		runtime_MSpanList_Remove(t);
@@ -304,6 +309,7 @@ MHeap_FreeLocked(MHeap *h, MSpan *s)
 		tp = (uintptr*)(t->start<<PageShift);
 		*sp |= *tp;	// propagate "needs zeroing" mark
 		s->npages += t->npages;
+		s->npreleased += t->npreleased;
 		h->map[p + s->npages - 1] = s;
 		runtime_MSpanList_Remove(t);
 		t->state = MSpanDead;
@@ -317,8 +323,86 @@ MHeap_FreeLocked(MHeap *h, MSpan *s)
 		runtime_MSpanList_Insert(&h->free[s->npages], s);
 	else
 		runtime_MSpanList_Insert(&h->large, s);
+}
 
-	// TODO(rsc): IncrementalScavenge() to return memory to OS.
+// Release (part of) unused memory to OS.
+// Goroutine created in runtime_schedinit.
+// Loop forever.
+void
+runtime_MHeap_Scavenger(void* dummy)
+{
+	MHeap *h;
+	MSpan *s, *list;
+	uint64 tick, now, forcegc, limit;
+	uint32 k, i;
+	uintptr released, sumreleased;
+	const byte *env;
+	bool trace;
+	Note note;
+
+	USED(dummy);
+
+	// If we go two minutes without a garbage collection, force one to run.
+	forcegc = 2*60*1e9;
+	// If a span goes unused for 5 minutes after a garbage collection,
+	// we hand it back to the operating system.
+	limit = 5*60*1e9;
+	// Make wake-up period small enough for the sampling to be correct.
+	if(forcegc < limit)
+		tick = forcegc/2;
+	else
+		tick = limit/2;
+
+	trace = false;
+	env = runtime_getenv("GOGCTRACE");
+	if(env != nil)
+		trace = runtime_atoi(env) > 0;
+
+	h = &runtime_mheap;
+	for(k=0;; k++) {
+		runtime_noteclear(&note);
+		runtime_entersyscall();
+		runtime_notetsleep(&note, tick);
+		runtime_exitsyscall();
+
+		runtime_lock(h);
+		now = runtime_nanotime();
+		if(now - mstats.last_gc > forcegc) {
+			runtime_unlock(h);
+			runtime_gc(1);
+			runtime_lock(h);
+			now = runtime_nanotime();
+			if (trace)
+				runtime_printf("scvg%d: GC forced\n", k);
+		}
+		sumreleased = 0;
+		for(i=0; i < nelem(h->free)+1; i++) {
+			if(i < nelem(h->free))
+				list = &h->free[i];
+			else
+				list = &h->large;
+			if(runtime_MSpanList_IsEmpty(list))
+				continue;
+			for(s=list->next; s != list; s=s->next) {
+				if(s->unusedsince != 0 && (now - s->unusedsince) > limit) {
+					released = (s->npages - s->npreleased) << PageShift;
+					mstats.heap_released += released;
+					sumreleased += released;
+					s->npreleased = s->npages;
+					runtime_SysUnused((void*)(s->start << PageShift), s->npages << PageShift);
+				}
+			}
+		}
+		runtime_unlock(h);
+
+		if(trace) {
+			if(sumreleased > 0)
+				runtime_printf("scvg%d: %p MB released\n", k, (void*)(sumreleased>>20));
+			runtime_printf("scvg%d: inuse: %lld, idle: %lld, sys: %lld, released: %lld, consumed: %lld (MB)\n",
+				k, (long long)(mstats.heap_inuse>>20), (long long)(mstats.heap_idle>>20), (long long)(mstats.heap_sys>>20),
+				(long long)(mstats.heap_released>>20), (long long)((mstats.heap_sys - mstats.heap_released)>>20));
+		}
+	}
 }
 
 // Initialize a new span with the given start and npages.
@@ -333,6 +417,8 @@ runtime_MSpan_Init(MSpan *span, PageID start, uintptr npages)
 	span->ref = 0;
 	span->sizeclass = 0;
 	span->state = 0;
+	span->unusedsince = 0;
+	span->npreleased = 0;
 }
 
 // Initialize an empty doubly-linked list.
diff --git a/libgo/runtime/mprof.goc b/libgo/runtime/mprof.goc
index 95e05fabeb3..e40dd61f784 100644
--- a/libgo/runtime/mprof.goc
+++ b/libgo/runtime/mprof.goc
@@ -26,6 +26,10 @@ struct Bucket
 	uintptr	frees;
 	uintptr	alloc_bytes;
 	uintptr	free_bytes;
+	uintptr	recent_allocs;  // since last gc
+	uintptr	recent_frees;
+	uintptr	recent_alloc_bytes;
+	uintptr	recent_free_bytes;
 	uintptr	hash;
 	uintptr	nstk;
 	uintptr	stk[1];
@@ -39,7 +43,7 @@ static uintptr bucketmem;
 
 // Return the bucket for stk[0:nstk], allocating new bucket if needed.
 static Bucket*
-stkbucket(uintptr *stk, int32 nstk)
+stkbucket(uintptr *stk, int32 nstk, bool alloc)
 {
 	int32 i;
 	uintptr h;
@@ -66,6 +70,9 @@ stkbucket(uintptr *stk, int32 nstk)
 		   runtime_mcmp((byte*)b->stk, (byte*)stk, nstk*sizeof stk[0]) == 0)
 			return b;
 
+	if(!alloc)
+		return nil;
+
 	b = runtime_mallocgc(sizeof *b + nstk*sizeof stk[0], FlagNoProfiling, 0, 1);
 	bucketmem += sizeof *b + nstk*sizeof stk[0];
 	runtime_memmove(b->stk, stk, nstk*sizeof stk[0]);
@@ -78,6 +85,26 @@ stkbucket(uintptr *stk, int32 nstk)
 	return b;
 }
 
+// Record that a gc just happened: all the 'recent' statistics are now real.
+void
+runtime_MProf_GC(void)
+{
+	Bucket *b;
+	
+	runtime_lock(&proflock);
+	for(b=buckets; b; b=b->allnext) {
+		b->allocs += b->recent_allocs;
+		b->frees += b->recent_frees;
+		b->alloc_bytes += b->recent_alloc_bytes;
+		b->free_bytes += b->recent_free_bytes;
+		b->recent_allocs = 0;
+		b->recent_frees = 0;
+		b->recent_alloc_bytes = 0;
+		b->recent_free_bytes = 0;
+	}
+	runtime_unlock(&proflock);
+}
+
 // Map from pointer to Bucket* that allocated it.
 // Three levels:
 //	Linked-list hash table for top N-20 bits.
@@ -204,9 +231,9 @@ runtime_MProf_Malloc(void *p, uintptr size)
 	nstk = 0;
 #endif
 	runtime_lock(&proflock);
-	b = stkbucket(stk, nstk);
-	b->allocs++;
-	b->alloc_bytes += size;
+	b = stkbucket(stk, nstk, true);
+	b->recent_allocs++;
+	b->recent_alloc_bytes += size;
 	setaddrbucket((uintptr)p, b);
 	runtime_unlock(&proflock);
 	m = runtime_m();
@@ -228,8 +255,8 @@ runtime_MProf_Free(void *p, uintptr size)
 	runtime_lock(&proflock);
 	b = getaddrbucket((uintptr)p);
 	if(b != nil) {
-		b->frees++;
-		b->free_bytes += size;
+		b->recent_frees++;
+		b->recent_free_bytes += size;
 	}
 	runtime_unlock(&proflock);
 	m = runtime_m();
@@ -293,13 +320,13 @@ runtime_MProf_Mark(void (*scan)(byte *, int64))
 	scan((byte*)&addrfree, sizeof addrfree);
 }
 
-// Must match ThreadProfileRecord in debug.go.
+// Must match StackRecord in debug.go.
 typedef struct TRecord TRecord;
 struct TRecord {
 	uintptr stk[32];
 };
 
-func ThreadProfile(p Slice) (n int32, ok bool) {
+func ThreadCreateProfile(p Slice) (n int32, ok bool) {
 	TRecord *r;
 	M *first, *m;
 	
@@ -317,3 +344,89 @@ func ThreadProfile(p Slice) (n int32, ok bool) {
 		}
 	}
 }
+
+func Stack(b Slice, all bool) (n int32) {
+	byte *pc, *sp;
+	
+	sp = runtime_getcallersp(&b);
+	pc = runtime_getcallerpc(&b);
+
+	if(all) {
+		runtime_semacquire(&runtime_worldsema);
+		runtime_m()->gcing = 1;
+		runtime_stoptheworld();
+	}
+
+	if(b.__count == 0)
+		n = 0;
+	else{
+		G* g = runtime_g();
+		g->writebuf = (byte*)b.__values;
+		g->writenbuf = b.__count;
+		USED(pc);
+		USED(sp);
+		// runtime_goroutineheader(g);
+		// runtime_traceback(pc, sp, 0, g);
+		// if(all)
+		//	runtime_tracebackothers(g);
+		n = b.__count - g->writenbuf;
+		g->writebuf = nil;
+		g->writenbuf = 0;
+	}
+	
+	if(all) {
+		runtime_m()->gcing = 0;
+		runtime_semrelease(&runtime_worldsema);
+		runtime_starttheworld(false);
+	}
+}
+
+static void
+saveg(byte *pc, byte *sp, G *g, TRecord *r)
+{
+	int32 n;
+
+	USED(pc);
+	USED(sp);
+	USED(g);
+	// n = runtime_gentraceback(pc, sp, 0, g, 0, r->stk, nelem(r->stk));
+	n = 0;
+	if((size_t)n < nelem(r->stk))
+		r->stk[n] = 0;
+}
+
+func GoroutineProfile(b Slice) (n int32, ok bool) {
+	byte *pc, *sp;
+	TRecord *r;
+	G *gp;
+	
+	sp = runtime_getcallersp(&b);
+	pc = runtime_getcallerpc(&b);
+	
+	ok = false;
+	n = runtime_gcount();
+	if(n <= b.__count) {
+		runtime_semacquire(&runtime_worldsema);
+		runtime_m()->gcing = 1;
+		runtime_stoptheworld();
+
+		n = runtime_gcount();
+		if(n <= b.__count) {
+			G* g = runtime_g();
+			ok = true;
+			r = (TRecord*)b.__values;
+			saveg(pc, sp, g, r++);
+			for(gp = runtime_allg; gp != nil; gp = gp->alllink) {
+				if(gp == g || gp->status == Gdead)
+					continue;
+				//saveg(gp->sched.pc, gp->sched.sp, gp, r++);
+				r++;
+			}
+		}
+	
+		runtime_m()->gcing = 0;
+		runtime_semrelease(&runtime_worldsema);
+		runtime_starttheworld(false);
+	}
+}
+
diff --git a/libgo/runtime/proc.c b/libgo/runtime/proc.c
index a4e4588299e..d0ae09c45a0 100644
--- a/libgo/runtime/proc.c
+++ b/libgo/runtime/proc.c
@@ -362,6 +362,9 @@ runtime_mcall(void (*pfn)(G*))
 	}
 }
 
+// Keep trace of scavenger's goroutine for deadlock detection.
+static G *scvg;
+
 // The bootstrap sequence is:
 //
 //	call osinit
@@ -413,6 +416,8 @@ runtime_schedinit(void)
 	// Can not enable GC until all roots are registered.
 	// mstats.enablegc = 1;
 	m->nomemprof--;
+
+	scvg = __go_go(runtime_MHeap_Scavenger, nil);
 }
 
 extern void main_init(void) __asm__ ("__go_init_main");
@@ -547,7 +552,7 @@ mcommoninit(M *m)
 	// Add to runtime_allm so garbage collector doesn't free m
 	// when it is just in a register or thread-local storage.
 	m->alllink = runtime_allm;
-	// runtime_Cgocalls() iterates over allm w/o schedlock,
+	// runtime_NumCgoCall() iterates over allm w/o schedlock,
 	// so we need to publish it safely.
 	runtime_atomicstorep(&runtime_allm, m);
 }
@@ -786,9 +791,12 @@ top:
 		mput(m);
 	}
 
-	v = runtime_atomicload(&runtime_sched.atomic);
-	if(runtime_sched.grunning == 0)
-		runtime_throw("all goroutines are asleep - deadlock!");
+	// Look for deadlock situation: one single active g which happens to be scvg.
+	if(runtime_sched.grunning == 1 && runtime_sched.gwait == 0) {
+		if(scvg->status == Grunning || scvg->status == Gsyscall)
+			runtime_throw("all goroutines are asleep - deadlock!");
+	}
+
 	m->nextg = nil;
 	m->waitnextg = 1;
 	runtime_noteclear(&m->havenextg);
@@ -797,6 +805,7 @@ top:
 	// Entersyscall might have decremented mcpu too, but if so
 	// it will see the waitstop and take the slow path.
 	// Exitsyscall never increments mcpu beyond mcpumax.
+	v = runtime_atomicload(&runtime_sched.atomic);
 	if(atomic_waitstop(v) && atomic_mcpu(v) <= atomic_mcpumax(v)) {
 		// set waitstop = 0 (known to be 1)
 		runtime_xadd(&runtime_sched.atomic, -1<<waitstopShift);
@@ -1472,11 +1481,17 @@ runtime_mid()
 	return m->id;
 }
 
-int32 runtime_Goroutines (void)
-  __asm__ ("libgo_runtime.runtime.Goroutines");
+int32 runtime_NumGoroutine (void)
+  __asm__ ("libgo_runtime.runtime.NumGoroutine");
+
+int32
+runtime_NumGoroutine()
+{
+	return runtime_sched.gcount;
+}
 
 int32
-runtime_Goroutines()
+runtime_gcount(void)
 {
 	return runtime_sched.gcount;
 }
diff --git a/libgo/runtime/runtime.h b/libgo/runtime/runtime.h
index 713af174491..113bb7163c5 100644
--- a/libgo/runtime/runtime.h
+++ b/libgo/runtime/runtime.h
@@ -143,6 +143,8 @@ struct	G
 	M*	lockedm;
 	M*	idlem;
 	// int32	sig;
+	int32	writenbuf;
+	byte*	writebuf;
 	// uintptr	sigcode0;
 	// uintptr	sigcode1;
 	// uintptr	sigpc;
@@ -189,9 +191,9 @@ struct	SigTab
 enum
 {
 	SigNotify = 1<<0,	// let signal.Notify have signal, even if from kernel
-	SigKill = 1<<1,  // if signal.Notify doesn't take it, exit quietly
-	SigThrow = 1<<2,  // if signal.Notify doesn't take it, exit loudly
-	SigPanic = 1<<3,  // if the signal is from the kernel, panic
+	SigKill = 1<<1,		// if signal.Notify doesn't take it, exit quietly
+	SigThrow = 1<<2,	// if signal.Notify doesn't take it, exit loudly
+	SigPanic = 1<<3,	// if the signal is from the kernel, panic
 	SigDefault = 1<<4,	// if the signal isn't explicitly requested, don't monitor it
 };
 
@@ -277,6 +279,7 @@ void	runtime_panicstring(const char*) __attribute__ ((noreturn));
 void*	runtime_mal(uintptr);
 void	runtime_schedinit(void);
 void	runtime_initsig(void);
+void	runtime_sigenable(uint32 sig);
 String	runtime_gostringnocopy(const byte*);
 void*	runtime_mstart(void*);
 G*	runtime_malg(int32, byte**, size_t*);
@@ -296,6 +299,7 @@ int64	runtime_cputicks(void);
 
 void	runtime_stoptheworld(void);
 void	runtime_starttheworld(bool);
+extern uint32 runtime_worldsema;
 G*	__go_go(void (*pfn)(void*), void*);
 
 /*
@@ -348,6 +352,7 @@ void	runtime_futexwakeup(uint32*, uint32);
 #define runtime_munmap munmap
 #define runtime_madvise madvise
 #define runtime_memclr(buf, size) __builtin_memset((buf), 0, (size))
+#define runtime_getcallerpc(p) __builtin_return_address(0)
 
 #ifdef __rtems__
 void __wrap_rtems_task_variable_add(void **);
@@ -373,8 +378,6 @@ void reflect_call(const struct __go_func_type *, const void *, _Bool, _Bool,
 #define runtime_exit(s) exit(s)
 MCache*	runtime_allocmcache(void);
 void	free(void *v);
-struct __go_func_type;
-bool	runtime_addfinalizer(void*, void(*fn)(void*), const struct __go_func_type *);
 #define runtime_cas(pval, old, new) __sync_bool_compare_and_swap (pval, old, new)
 #define runtime_casp(pval, old, new) __sync_bool_compare_and_swap (pval, old, new)
 #define runtime_xadd(p, v) __sync_add_and_fetch (p, v)
@@ -384,6 +387,11 @@ bool	runtime_addfinalizer(void*, void(*fn)(void*), const struct __go_func_type *
 #define runtime_atomicloadp(p) __atomic_load_n (p, __ATOMIC_SEQ_CST)
 #define runtime_atomicstorep(p, v) __atomic_store_n (p, v, __ATOMIC_SEQ_CST)
 
+struct __go_func_type;
+bool	runtime_addfinalizer(void*, void(*fn)(void*), const struct __go_func_type *);
+#define runtime_getcallersp(p) __builtin_frame_address(1)
+int32	runtime_mcount(void);
+int32	runtime_gcount(void);
 void	runtime_dopanic(int32) __attribute__ ((noreturn));
 void	runtime_startpanic(void);
 void	runtime_ready(G*);
diff --git a/libgo/runtime/sema.goc b/libgo/runtime/sema.goc
index dd58cf38fb8..ff9c4f2e19e 100644
--- a/libgo/runtime/sema.goc
+++ b/libgo/runtime/sema.goc
@@ -17,7 +17,7 @@
 // See Mullender and Cox, ``Semaphores in Plan 9,''
 // http://swtch.com/semaphore.pdf
 
-package runtime
+package sync
 #include "runtime.h"
 #include "arch.h"
 
@@ -172,10 +172,10 @@ runtime_semrelease(uint32 volatile *addr)
 		runtime_ready(s->g);
 }
 
-func Semacquire(addr *uint32) {
+func runtime_Semacquire(addr *uint32) {
 	runtime_semacquire(addr);
 }
 
-func Semrelease(addr *uint32) {
+func runtime_Semrelease(addr *uint32) {
 	runtime_semrelease(addr);
 }
diff --git a/libgo/runtime/sigqueue.goc b/libgo/runtime/sigqueue.goc
index c550a4ebe9b..be7c5920cbc 100644
--- a/libgo/runtime/sigqueue.goc
+++ b/libgo/runtime/sigqueue.goc
@@ -142,10 +142,12 @@ func signal_enable(s uint32) {
 		// Special case: want everything.
 		for(i=0; (size_t)i<nelem(sig.wanted); i++)
 			sig.wanted[i] = ~(uint32)0;
+		runtime_sigenable(s);
 		return;
 	}
 
 	if(s >= nelem(sig.wanted)*32)
 		return;
 	sig.wanted[s/32] |= 1U<<(s&31);
+	runtime_sigenable(s);
 }
author	ian <ian@138bc75d-0d04-0410-961f-82ee72b054a4>	2012-03-02 20:01:37 +0000
committer	ian <ian@138bc75d-0d04-0410-961f-82ee72b054a4>	2012-03-02 20:01:37 +0000
commit	ef10b1dda693467283a3645a5da610e810149764 (patch)
tree	3eeb8918d39d675108073c8b76d6dd10586a608c /libgo
parent	ea6ad4ae9afbd45b5c19aadab39ddbf1db0d50f8 (diff)
download	gcc-ef10b1dda693467283a3645a5da610e810149764.tar.gz