obtained gcc-4.6.4.tar.bz2 from upstream website;upstream

verified gcc-4.6.4.tar.bz2.sig;
imported gcc-4.6.4 source tree from verified upstream tarball.

downloading a git-generated archive based on the 'upstream' tag
should provide you with a source tree that is binary identical
to the one extracted from the above tarball.

if you have obtained the source via the command 'git clone',
however, do note that line-endings of files in your working
directory might differ from line-endings of the respective
files in the upstream repository.

6 files changed, 421 insertions, 0 deletions

diff --git a/libgo/go/compress/zlib/reader.go b/libgo/go/compress/zlib/reader.go
new file mode 100644
index 000000000..721f6ec55
--- /dev/null
+++ b/libgo/go/compress/zlib/reader.go
@@ -0,0 +1,112 @@
+// 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.
+
+/*
+The zlib package implements reading and writing of zlib
+format compressed data, as specified in RFC 1950.
+
+The implementation provides filters that uncompress during reading
+and compress during writing.  For example, to write compressed data
+to a buffer:
+
+	var b bytes.Buffer
+	w, err := zlib.NewWriter(&b)
+	w.Write([]byte("hello, world\n"))
+	w.Close()
+
+and to read that data back:
+
+	r, err := zlib.NewReader(&b)
+	io.Copy(os.Stdout, r)
+	r.Close()
+*/
+package zlib
+
+import (
+	"bufio"
+	"compress/flate"
+	"hash"
+	"hash/adler32"
+	"io"
+	"os"
+)
+
+const zlibDeflate = 8
+
+var ChecksumError os.Error = os.ErrorString("zlib checksum error")
+var HeaderError os.Error = os.ErrorString("invalid zlib header")
+var UnsupportedError os.Error = os.ErrorString("unsupported zlib format")
+
+type reader struct {
+	r            flate.Reader
+	decompressor io.ReadCloser
+	digest       hash.Hash32
+	err          os.Error
+	scratch      [4]byte
+}
+
+// NewReader creates a new io.ReadCloser that satisfies reads by decompressing data read from r.
+// The implementation buffers input and may read more data than necessary from r.
+// It is the caller's responsibility to call Close on the ReadCloser when done.
+func NewReader(r io.Reader) (io.ReadCloser, os.Error) {
+	z := new(reader)
+	if fr, ok := r.(flate.Reader); ok {
+		z.r = fr
+	} else {
+		z.r = bufio.NewReader(r)
+	}
+	_, err := io.ReadFull(z.r, z.scratch[0:2])
+	if err != nil {
+		return nil, err
+	}
+	h := uint(z.scratch[0])<<8 | uint(z.scratch[1])
+	if (z.scratch[0]&0x0f != zlibDeflate) || (h%31 != 0) {
+		return nil, HeaderError
+	}
+	if z.scratch[1]&0x20 != 0 {
+		// BUG(nigeltao): The zlib package does not implement the FDICT flag.
+		return nil, UnsupportedError
+	}
+	z.digest = adler32.New()
+	z.decompressor = flate.NewReader(z.r)
+	return z, nil
+}
+
+func (z *reader) Read(p []byte) (n int, err os.Error) {
+	if z.err != nil {
+		return 0, z.err
+	}
+	if len(p) == 0 {
+		return 0, nil
+	}
+
+	n, err = z.decompressor.Read(p)
+	z.digest.Write(p[0:n])
+	if n != 0 || err != os.EOF {
+		z.err = err
+		return
+	}
+
+	// Finished file; check checksum.
+	if _, err := io.ReadFull(z.r, z.scratch[0:4]); err != nil {
+		z.err = err
+		return 0, err
+	}
+	// ZLIB (RFC 1950) is big-endian, unlike GZIP (RFC 1952).
+	checksum := uint32(z.scratch[0])<<24 | uint32(z.scratch[1])<<16 | uint32(z.scratch[2])<<8 | uint32(z.scratch[3])
+	if checksum != z.digest.Sum32() {
+		z.err = ChecksumError
+		return 0, z.err
+	}
+	return
+}
+
+// Calling Close does not close the wrapped io.Reader originally passed to NewReader.
+func (z *reader) Close() os.Error {
+	if z.err != nil {
+		return z.err
+	}
+	z.err = z.decompressor.Close()
+	return z.err
+}
diff --git a/libgo/go/compress/zlib/reader_test.go b/libgo/go/compress/zlib/reader_test.go
new file mode 100644
index 000000000..eaefc3a36
--- /dev/null
+++ b/libgo/go/compress/zlib/reader_test.go
@@ -0,0 +1,95 @@
+// 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.
+
+package zlib
+
+import (
+	"bytes"
+	"io"
+	"os"
+	"testing"
+)
+
+type zlibTest struct {
+	desc       string
+	raw        string
+	compressed []byte
+	err        os.Error
+}
+
+// Compare-to-golden test data was generated by the ZLIB example program at
+// http://www.zlib.net/zpipe.c
+
+var zlibTests = []zlibTest{
+	{
+		"empty",
+		"",
+		[]byte{0x78, 0x9c, 0x03, 0x00, 0x00, 0x00, 0x00, 0x01},
+		nil,
+	},
+	{
+		"goodbye",
+		"goodbye, world",
+		[]byte{
+			0x78, 0x9c, 0x4b, 0xcf, 0xcf, 0x4f, 0x49, 0xaa,
+			0x4c, 0xd5, 0x51, 0x28, 0xcf, 0x2f, 0xca, 0x49,
+			0x01, 0x00, 0x28, 0xa5, 0x05, 0x5e,
+		},
+		nil,
+	},
+	{
+		"bad header",
+		"",
+		[]byte{0x78, 0x9f, 0x03, 0x00, 0x00, 0x00, 0x00, 0x01},
+		HeaderError,
+	},
+	{
+		"bad checksum",
+		"",
+		[]byte{0x78, 0x9c, 0x03, 0x00, 0x00, 0x00, 0x00, 0xff},
+		ChecksumError,
+	},
+	{
+		"not enough data",
+		"",
+		[]byte{0x78, 0x9c, 0x03, 0x00, 0x00, 0x00},
+		io.ErrUnexpectedEOF,
+	},
+	{
+		"excess data is silently ignored",
+		"",
+		[]byte{
+			0x78, 0x9c, 0x03, 0x00, 0x00, 0x00, 0x00, 0x01,
+			0x78, 0x9c, 0xff,
+		},
+		nil,
+	},
+}
+
+func TestDecompressor(t *testing.T) {
+	b := new(bytes.Buffer)
+	for _, tt := range zlibTests {
+		in := bytes.NewBuffer(tt.compressed)
+		zlib, err := NewReader(in)
+		if err != nil {
+			if err != tt.err {
+				t.Errorf("%s: NewReader: %s", tt.desc, err)
+			}
+			continue
+		}
+		defer zlib.Close()
+		b.Reset()
+		n, err := io.Copy(b, zlib)
+		if err != nil {
+			if err != tt.err {
+				t.Errorf("%s: io.Copy: %v want %v", tt.desc, err, tt.err)
+			}
+			continue
+		}
+		s := b.String()
+		if s != tt.raw {
+			t.Errorf("%s: got %d-byte %q want %d-byte %q", tt.desc, n, s, len(tt.raw), tt.raw)
+		}
+	}
+}
diff --git a/libgo/go/compress/zlib/testdata/e.txt b/libgo/go/compress/zlib/testdata/e.txt
new file mode 100644
index 000000000..76cf2a7b6
--- /dev/null
+++ b/libgo/go/compress/zlib/testdata/e.txt
@@ -0,0 +1 @@
+2.71828182845904523536028747135266249775724709369995957496696762772407663035354759457138217852516642742746639193200305992181741359662904357290033429526059563073813232862794349076323382988075319525101901157383418793070215408914993488416750924476146066808226480016847741185374234544243710753907774499206955170276183860626133138458300075204493382656029760673711320070932870912744374704723069697720931014169283681902551510865746377211125238978442505695369677078544996996794686445490598793163688923009879312773617821542499922957635148220826989519366803318252886939849646510582093923982948879332036250944311730123819706841614039701983767932068328237646480429531180232878250981945581530175671736133206981125099618188159304169035159888851934580727386673858942287922849989208680582574927961048419844436346324496848756023362482704197862320900216099023530436994184914631409343173814364054625315209618369088870701676839642437814059271456354906130310720851038375051011574770417189861068739696552126715468895703503540212340784981933432106817012100562788023519303322474501585390473041995777709350366041699732972508868769664035557071622684471625607988265178713419512466520103059212366771943252786753985589448969709640975459185695638023637016211204774272283648961342251644507818244235294863637214174023889344124796357437026375529444833799801612549227850925778256209262264832627793338656648162772516401910590049164499828931505660472580277863186415519565324425869829469593080191529872117255634754639644791014590409058629849679128740687050489585867174798546677575732056812884592054133405392200011378630094556068816674001698420558040336379537645203040243225661352783695117788386387443966253224985065499588623428189970773327617178392803494650143455889707194258639877275471096295374152111513683506275260232648472870392076431005958411661205452970302364725492966693811513732275364509888903136020572481765851180630364428123149655070475102544650117272115551948668508003685322818315219600373562527944951582841882947876108526398139559900673764829224437528718462457803619298197139914756448826260390338144182326251509748279877799643730899703888677822713836057729788241256119071766394650706330452795466185509666618566470971134447401607046262156807174818778443714369882185596709591025968620023537185887485696522000503117343920732113908032936344797273559552773490717837934216370120500545132638354400018632399149070547977805669785335804896690629511943247309958765523681285904138324116072260299833053537087613893963917795745401613722361878936526053815584158718692553860616477983402543512843961294603529133259427949043372990857315802909586313826832914771163963370924003168945863606064584592512699465572483918656420975268508230754425459937691704197778008536273094171016343490769642372229435236612557250881477922315197477806056967253801718077636034624592787784658506560507808442115296975218908740196609066518035165017925046195013665854366327125496399085491442000145747608193022120660243300964127048943903971771951806990869986066365832322787093765022601492910115171776359446020232493002804018677239102880978666056511832600436885088171572386698422422010249505518816948032210025154264946398128736776589276881635983124778865201411741109136011649950766290779436460058519419985601626479076153210387275571269925182756879893027617611461625493564959037980458381823233686120162437365698467037858533052758333379399075216606923805336988795651372855938834998947074161815501253970646481719467083481972144888987906765037959036696724949925452790337296361626589760394985767413973594410237443297093554779826296145914429364514286171585873397467918975712119561873857836447584484235555810500256114923915188930994634284139360803830916628188115037152849670597416256282360921680751501777253874025642534708790891372917228286115159156837252416307722544063378759310598267609442032619242853170187817729602354130606721360460003896610936470951414171857770141806064436368154644400533160877831431744408119494229755993140118886833148328027065538330046932901157441475631399972217038046170928945790962716622607407187499753592127560844147378233032703301682371936480021732857349359475643341299430248502357322145978432826414216848787216733670106150942434569844018733128101079451272237378861260581656680537143961278887325273738903928905068653241380627960259303877276977837928684093253658807339884572187460210053114833513238500478271693762180049047955979592905916554705057775143081751126989851884087185640260353055837378324229241856256442550226721559802740126179719280471396006891638286652770097527670697770364392602243728418408832518487704726384403795301669054659374616193238403638931313643271376888410268112198912752230562567562547017250863497653672886059667527408686274079128565769963137897530346606166698042182677245605306607738996242183408598820718646826232150802882863597468396543588566855037731312965879758105012149162076567699506597153447634703208532156036748286083786568030730626576334697742956346437167093971930608769634953288468336130388294310408002968738691170666661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diff --git a/libgo/go/compress/zlib/testdata/pi.txt b/libgo/go/compress/zlib/testdata/pi.txt
new file mode 100644
index 000000000..58d8f3b6d
--- /dev/null
+++ b/libgo/go/compress/zlib/testdata/pi.txt
@@ -0,0 +1 @@
+3.14159265358979323846264338327950288419716939937510582097494459230781640628620899862803482534211706798214808651328230664709384460955058223172535940812848111745028410270193852110555964462294895493038196442881097566593344612847564823378678316527120190914564856692346034861045432664821339360726024914127372458700660631558817488152092096282925409171536436789259036001133053054882046652138414695194151160943305727036575959195309218611738193261179310511854807446237996274956735188575272489122793818301194912983367336244065664308602139494639522473719070217986094370277053921717629317675238467481846766940513200056812714526356082778577134275778960917363717872146844090122495343014654958537105079227968925892354201995611212902196086403441815981362977477130996051870721134999999837297804995105973173281609631859502445945534690830264252230825334468503526193118817101000313783875288658753320838142061717766914730359825349042875546873115956286388235378759375195778185778053217122680661300192787661119590921642019893809525720106548586327886593615338182796823030195203530185296899577362259941389124972177528347913151557485724245415069595082953311686172785588907509838175463746493931925506040092770167113900984882401285836160356370766010471018194295559619894676783744944825537977472684710404753464620804668425906949129331367702898915210475216205696602405803815019351125338243003558764024749647326391419927260426992279678235478163600934172164121992458631503028618297455570674983850549458858692699569092721079750930295532116534498720275596023648066549911988183479775356636980742654252786255181841757467289097777279380008164706001614524919217321721477235014144197356854816136115735255213347574184946843852332390739414333454776241686251898356948556209921922218427255025425688767179049460165346680498862723279178608578438382796797668145410095388378636095068006422512520511739298489608412848862694560424196528502221066118630674427862203919494504712371378696095636437191728746776465757396241389086583264599581339047802759009946576407895126946839835259570982582262052248940772671947826848260147699090264013639443745530506820349625245174939965143142980919065925093722169646151570985838741059788595977297549893016175392846813826868386894277415599185592524595395943104997252468084598727364469584865383673622262609912460805124388439045124413654976278079771569143599770012961608944169486855584840635342207222582848864815845602850601684273945226746767889525213852254995466672782398645659611635488623057745649803559363456817432411251507606947945109659609402522887971089314566913686722874894056010150330861792868092087476091782493858900971490967598526136554978189312978482168299894872265880485756401427047755513237964145152374623436454285844479526586782105114135473573952311342716610213596953623144295248493718711014576540359027993440374200731057853906219838744780847848968332144571386875194350643021845319104848100537061468067491927819119793995206141966342875444064374512371819217999839101591956181467514269123974894090718649423196156794520809514655022523160388193014209376213785595663893778708303906979207734672218256259966150142150306803844773454920260541466592520149744285073251866600213243408819071048633173464965145390579626856100550810665879699816357473638405257145910289706414011097120628043903975951567715770042033786993600723055876317635942187312514712053292819182618612586732157919841484882916447060957527069572209175671167229109816909152801735067127485832228718352093539657251210835791513698820914442100675103346711031412671113699086585163983150197016515116851714376576183515565088490998985998238734552833163550764791853589322618548963213293308985706420467525907091548141654985946163718027098199430992448895757128289059232332609729971208443357326548938239119325974636673058360414281388303203824903758985243744170291327656180937734440307074692112019130203303801976211011004492932151608424448596376698389522868478312355265821314495768572624334418930396864262434107732269780280731891544110104468232527162010526522721116603966655730925471105578537634668206531098965269186205647693125705863566201855810072936065987648611791045334885034611365768675324944166803962657978771855608455296541266540853061434443185867697514566140680070023787765913440171274947042056223053899456131407112700040785473326993908145466464588079727082668306343285878569830523580893306575740679545716377525420211495576158140025012622859413021647155097925923099079654737612551765675135751782966645477917450112996148903046399471329621073404375189573596145890193897131117904297828564750320319869151402870808599048010941214722131794764777262241425485454033215718530614228813758504306332175182979866223717215916077166925474873898665494945011465406284336639379003976926567214638530673609657120918076383271664162748888007869256029022847210403172118608204190004229661711963779213375751149595015660496318629472654736425230817703675159067350235072835405670403867435136222247715891504953098444893330963408780769325993978054193414473774418426312986080998886874132604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diff --git a/libgo/go/compress/zlib/writer.go b/libgo/go/compress/zlib/writer.go
new file mode 100644
index 000000000..031586cd2
--- /dev/null
+++ b/libgo/go/compress/zlib/writer.go
@@ -0,0 +1,106 @@
+// 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.
+
+package zlib
+
+import (
+	"compress/flate"
+	"hash"
+	"hash/adler32"
+	"io"
+	"os"
+)
+
+// These constants are copied from the flate package, so that code that imports
+// "compress/zlib" does not also have to import "compress/flate".
+const (
+	NoCompression      = flate.NoCompression
+	BestSpeed          = flate.BestSpeed
+	BestCompression    = flate.BestCompression
+	DefaultCompression = flate.DefaultCompression
+)
+
+type writer struct {
+	w          io.Writer
+	compressor io.WriteCloser
+	digest     hash.Hash32
+	err        os.Error
+	scratch    [4]byte
+}
+
+// NewWriter calls NewWriterLevel with the default compression level.
+func NewWriter(w io.Writer) (io.WriteCloser, os.Error) {
+	return NewWriterLevel(w, DefaultCompression)
+}
+
+// NewWriterLevel creates a new io.WriteCloser that satisfies writes by compressing data written to w.
+// It is the caller's responsibility to call Close on the WriteCloser when done.
+// level is the compression level, which can be DefaultCompression, NoCompression,
+// or any integer value between BestSpeed and BestCompression (inclusive).
+func NewWriterLevel(w io.Writer, level int) (io.WriteCloser, os.Error) {
+	z := new(writer)
+	// ZLIB has a two-byte header (as documented in RFC 1950).
+	// The first four bits is the CINFO (compression info), which is 7 for the default deflate window size.
+	// The next four bits is the CM (compression method), which is 8 for deflate.
+	z.scratch[0] = 0x78
+	// The next two bits is the FLEVEL (compression level). The four values are:
+	// 0=fastest, 1=fast, 2=default, 3=best.
+	// The next bit, FDICT, is unused, in this implementation.
+	// The final five FCHECK bits form a mod-31 checksum.
+	switch level {
+	case 0, 1:
+		z.scratch[1] = 0x01
+	case 2, 3, 4, 5:
+		z.scratch[1] = 0x5e
+	case 6, -1:
+		z.scratch[1] = 0x9c
+	case 7, 8, 9:
+		z.scratch[1] = 0xda
+	default:
+		return nil, os.NewError("level out of range")
+	}
+	_, err := w.Write(z.scratch[0:2])
+	if err != nil {
+		return nil, err
+	}
+	z.w = w
+	z.compressor = flate.NewWriter(w, level)
+	z.digest = adler32.New()
+	return z, nil
+}
+
+func (z *writer) Write(p []byte) (n int, err os.Error) {
+	if z.err != nil {
+		return 0, z.err
+	}
+	if len(p) == 0 {
+		return 0, nil
+	}
+	n, err = z.compressor.Write(p)
+	if err != nil {
+		z.err = err
+		return
+	}
+	z.digest.Write(p)
+	return
+}
+
+// Calling Close does not close the wrapped io.Writer originally passed to NewWriter.
+func (z *writer) Close() os.Error {
+	if z.err != nil {
+		return z.err
+	}
+	z.err = z.compressor.Close()
+	if z.err != nil {
+		return z.err
+	}
+	checksum := z.digest.Sum32()
+	// ZLIB (RFC 1950) is big-endian, unlike GZIP (RFC 1952).
+	z.scratch[0] = uint8(checksum >> 24)
+	z.scratch[1] = uint8(checksum >> 16)
+	z.scratch[2] = uint8(checksum >> 8)
+	z.scratch[3] = uint8(checksum >> 0)
+	_, z.err = z.w.Write(z.scratch[0:4])
+	return z.err
+}
diff --git a/libgo/go/compress/zlib/writer_test.go b/libgo/go/compress/zlib/writer_test.go
new file mode 100644
index 000000000..fa9e78e8e
--- /dev/null
+++ b/libgo/go/compress/zlib/writer_test.go
@@ -0,0 +1,106 @@
+// 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.
+
+package zlib
+
+import (
+	"io"
+	"io/ioutil"
+	"os"
+	"testing"
+)
+
+var filenames = []string{
+	"testdata/e.txt",
+	"testdata/pi.txt",
+}
+
+// Tests that compressing and then decompressing the given file at the given compression level
+// yields equivalent bytes to the original file.
+func testFileLevel(t *testing.T, fn string, level int) {
+	// Read the file, as golden output.
+	golden, err := os.Open(fn, os.O_RDONLY, 0444)
+	if err != nil {
+		t.Errorf("%s (level=%d): %v", fn, level, err)
+		return
+	}
+	defer golden.Close()
+
+	// Read the file again, and push it through a pipe that compresses at the write end, and decompresses at the read end.
+	raw, err := os.Open(fn, os.O_RDONLY, 0444)
+	if err != nil {
+		t.Errorf("%s (level=%d): %v", fn, level, err)
+		return
+	}
+	piper, pipew := io.Pipe()
+	defer piper.Close()
+	go func() {
+		defer raw.Close()
+		defer pipew.Close()
+		zlibw, err := NewWriterLevel(pipew, level)
+		if err != nil {
+			t.Errorf("%s (level=%d): %v", fn, level, err)
+			return
+		}
+		defer zlibw.Close()
+		var b [1024]byte
+		for {
+			n, err0 := raw.Read(b[0:])
+			if err0 != nil && err0 != os.EOF {
+				t.Errorf("%s (level=%d): %v", fn, level, err0)
+				return
+			}
+			_, err1 := zlibw.Write(b[0:n])
+			if err1 == os.EPIPE {
+				// Fail, but do not report the error, as some other (presumably reportable) error broke the pipe.
+				return
+			}
+			if err1 != nil {
+				t.Errorf("%s (level=%d): %v", fn, level, err1)
+				return
+			}
+			if err0 == os.EOF {
+				break
+			}
+		}
+	}()
+	zlibr, err := NewReader(piper)
+	if err != nil {
+		t.Errorf("%s (level=%d): %v", fn, level, err)
+		return
+	}
+	defer zlibr.Close()
+
+	// Compare the two.
+	b0, err0 := ioutil.ReadAll(golden)
+	b1, err1 := ioutil.ReadAll(zlibr)
+	if err0 != nil {
+		t.Errorf("%s (level=%d): %v", fn, level, err0)
+		return
+	}
+	if err1 != nil {
+		t.Errorf("%s (level=%d): %v", fn, level, err1)
+		return
+	}
+	if len(b0) != len(b1) {
+		t.Errorf("%s (level=%d): length mismatch %d versus %d", fn, level, len(b0), len(b1))
+		return
+	}
+	for i := 0; i < len(b0); i++ {
+		if b0[i] != b1[i] {
+			t.Errorf("%s (level=%d): mismatch at %d, 0x%02x versus 0x%02x\n", fn, level, i, b0[i], b1[i])
+			return
+		}
+	}
+}
+
+func TestWriter(t *testing.T) {
+	for _, fn := range filenames {
+		testFileLevel(t, fn, DefaultCompression)
+		testFileLevel(t, fn, NoCompression)
+		for level := BestSpeed; level <= BestCompression; level++ {
+			testFileLevel(t, fn, level)
+		}
+	}
+}