[release-branch.go1.23] go1.23.3

Change-Id: I065005a4a18f801d09ad3ebc886e90a6dd1df69a
Reviewed-on: https://go-review.googlesource.com/c/go/+/626137
Reviewed-by: Carlos Amedee <carlos@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Gopher Robot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>

.github/ISSUE_TEMPLATE/11-language-change.yml

@@ -1,7 +1,7 @@
 name: Language Change Proposals
 description: Changes to the language
-labels: ["Proposal", "LanguageChange", "LanguageChangeReview"]
-title: "proposal: spec: proposal title"
+labels: ["Proposal", "v2", "LanguageChange"]
+title: "proposal: Go 2: proposal title"
 
 
 body:

.gitignore

@@ -37,7 +37,7 @@ _testmain.go
 /src/go/build/zcgo.go
 /src/go/doc/headscan
 /src/internal/buildcfg/zbootstrap.go
-/src/internal/runtime/sys/zversion.go
+/src/runtime/internal/sys/zversion.go
 /src/unicode/maketables
 /src/time/tzdata/zzipdata.go
 /test.out

LICENSE

@@ -1,4 +1,4 @@
-Copyright 2009 The Go Authors.
+Copyright (c) 2009 The Go Authors. All rights reserved.
 
 Redistribution and use in source and binary forms, with or without
 modification, are permitted provided that the following conditions are
@@ -10,7 +10,7 @@ notice, this list of conditions and the following disclaimer.
 copyright notice, this list of conditions and the following disclaimer
 in the documentation and/or other materials provided with the
 distribution.
-   * Neither the name of Google LLC nor the names of its
+   * Neither the name of Google Inc. nor the names of its
 contributors may be used to endorse or promote products derived from
 this software without specific prior written permission.
 

VERSION

@@ -0,0 +1,2 @@
+go1.23.3
+time 2024-11-06T18:46:45Z

api/go1.24.txt

@@ -1,223 +0,0 @@
-pkg bytes, func FieldsFuncSeq([]uint8, func(int32) bool) iter.Seq[[]uint8] #61901
-pkg bytes, func FieldsSeq([]uint8) iter.Seq[[]uint8] #61901
-pkg bytes, func Lines([]uint8) iter.Seq[[]uint8] #61901
-pkg bytes, func SplitAfterSeq([]uint8, []uint8) iter.Seq[[]uint8] #61901
-pkg bytes, func SplitSeq([]uint8, []uint8) iter.Seq[[]uint8] #61901
-pkg crypto/cipher, func NewCFBDecrypter //deprecated #69445
-pkg crypto/cipher, func NewCFBEncrypter //deprecated #69445
-pkg crypto/cipher, func NewGCMWithRandomNonce(Block) (AEAD, error) #69981
-pkg crypto/cipher, func NewOFB //deprecated #69445
-pkg crypto/fips140, func Enabled() bool #70123
-pkg crypto/hkdf, func Expand[$0 hash.Hash](func() $0, []uint8, string, int) ([]uint8, error) #61477
-pkg crypto/hkdf, func Extract[$0 hash.Hash](func() $0, []uint8, []uint8) ([]uint8, error) #61477
-pkg crypto/hkdf, func Key[$0 hash.Hash](func() $0, []uint8, []uint8, string, int) ([]uint8, error) #61477
-pkg crypto/mlkem, const CiphertextSize1024 = 1568 #70122
-pkg crypto/mlkem, const CiphertextSize1024 ideal-int #70122
-pkg crypto/mlkem, const CiphertextSize768 = 1088 #70122
-pkg crypto/mlkem, const CiphertextSize768 ideal-int #70122
-pkg crypto/mlkem, const EncapsulationKeySize1024 = 1568 #70122
-pkg crypto/mlkem, const EncapsulationKeySize1024 ideal-int #70122
-pkg crypto/mlkem, const EncapsulationKeySize768 = 1184 #70122
-pkg crypto/mlkem, const EncapsulationKeySize768 ideal-int #70122
-pkg crypto/mlkem, const SeedSize = 64 #70122
-pkg crypto/mlkem, const SeedSize ideal-int #70122
-pkg crypto/mlkem, const SharedKeySize = 32 #70122
-pkg crypto/mlkem, const SharedKeySize ideal-int #70122
-pkg crypto/mlkem, func GenerateKey1024() (*DecapsulationKey1024, error) #70122
-pkg crypto/mlkem, func GenerateKey768() (*DecapsulationKey768, error) #70122
-pkg crypto/mlkem, func NewDecapsulationKey1024([]uint8) (*DecapsulationKey1024, error) #70122
-pkg crypto/mlkem, func NewDecapsulationKey768([]uint8) (*DecapsulationKey768, error) #70122
-pkg crypto/mlkem, func NewEncapsulationKey1024([]uint8) (*EncapsulationKey1024, error) #70122
-pkg crypto/mlkem, func NewEncapsulationKey768([]uint8) (*EncapsulationKey768, error) #70122
-pkg crypto/mlkem, method (*DecapsulationKey1024) Bytes() []uint8 #70122
-pkg crypto/mlkem, method (*DecapsulationKey1024) Decapsulate([]uint8) ([]uint8, error) #70122
-pkg crypto/mlkem, method (*DecapsulationKey1024) EncapsulationKey() *EncapsulationKey1024 #70122
-pkg crypto/mlkem, method (*DecapsulationKey768) Bytes() []uint8 #70122
-pkg crypto/mlkem, method (*DecapsulationKey768) Decapsulate([]uint8) ([]uint8, error) #70122
-pkg crypto/mlkem, method (*DecapsulationKey768) EncapsulationKey() *EncapsulationKey768 #70122
-pkg crypto/mlkem, method (*EncapsulationKey1024) Bytes() []uint8 #70122
-pkg crypto/mlkem, method (*EncapsulationKey1024) Encapsulate() ([]uint8, []uint8) #70122
-pkg crypto/mlkem, method (*EncapsulationKey768) Bytes() []uint8 #70122
-pkg crypto/mlkem, method (*EncapsulationKey768) Encapsulate() ([]uint8, []uint8) #70122
-pkg crypto/mlkem, type DecapsulationKey1024 struct #70122
-pkg crypto/mlkem, type DecapsulationKey768 struct #70122
-pkg crypto/mlkem, type EncapsulationKey1024 struct #70122
-pkg crypto/mlkem, type EncapsulationKey768 struct #70122
-pkg crypto/pbkdf2, func Key[$0 hash.Hash](func() $0, string, []uint8, int, int) ([]uint8, error) #69488
-pkg crypto/rand, func Text() string #67057
-pkg crypto/sha3, func New224() *SHA3 #69982
-pkg crypto/sha3, func New256() *SHA3 #69982
-pkg crypto/sha3, func New384() *SHA3 #69982
-pkg crypto/sha3, func New512() *SHA3 #69982
-pkg crypto/sha3, func NewCSHAKE128([]uint8, []uint8) *SHAKE #69982
-pkg crypto/sha3, func NewCSHAKE256([]uint8, []uint8) *SHAKE #69982
-pkg crypto/sha3, func NewSHAKE128() *SHAKE #69982
-pkg crypto/sha3, func NewSHAKE256() *SHAKE #69982
-pkg crypto/sha3, func Sum224([]uint8) [28]uint8 #69982
-pkg crypto/sha3, func Sum256([]uint8) [32]uint8 #69982
-pkg crypto/sha3, func Sum384([]uint8) [48]uint8 #69982
-pkg crypto/sha3, func Sum512([]uint8) [64]uint8 #69982
-pkg crypto/sha3, func SumSHAKE128([]uint8, int) []uint8 #69982
-pkg crypto/sha3, func SumSHAKE256([]uint8, int) []uint8 #69982
-pkg crypto/sha3, method (*SHA3) AppendBinary([]uint8) ([]uint8, error) #69982
-pkg crypto/sha3, method (*SHA3) BlockSize() int #69982
-pkg crypto/sha3, method (*SHA3) MarshalBinary() ([]uint8, error) #69982
-pkg crypto/sha3, method (*SHA3) Reset() #69982
-pkg crypto/sha3, method (*SHA3) Size() int #69982
-pkg crypto/sha3, method (*SHA3) Sum([]uint8) []uint8 #69982
-pkg crypto/sha3, method (*SHA3) UnmarshalBinary([]uint8) error #69982
-pkg crypto/sha3, method (*SHA3) Write([]uint8) (int, error) #69982
-pkg crypto/sha3, method (*SHAKE) AppendBinary([]uint8) ([]uint8, error) #69982
-pkg crypto/sha3, method (*SHAKE) BlockSize() int #69982
-pkg crypto/sha3, method (*SHAKE) MarshalBinary() ([]uint8, error) #69982
-pkg crypto/sha3, method (*SHAKE) Read([]uint8) (int, error) #69982
-pkg crypto/sha3, method (*SHAKE) Reset() #69982
-pkg crypto/sha3, method (*SHAKE) UnmarshalBinary([]uint8) error #69982
-pkg crypto/sha3, method (*SHAKE) Write([]uint8) (int, error) #69982
-pkg crypto/sha3, type SHA3 struct #69982
-pkg crypto/sha3, type SHAKE struct #69982
-pkg crypto/subtle, func WithDataIndependentTiming(func()) #66450
-pkg crypto/tls, const X25519MLKEM768 = 4588 #69985
-pkg crypto/tls, const X25519MLKEM768 CurveID #69985
-pkg crypto/tls, type ClientHelloInfo struct, Extensions []uint16 #32936
-pkg crypto/tls, type Config struct, EncryptedClientHelloKeys []EncryptedClientHelloKey #68500
-pkg crypto/tls, type EncryptedClientHelloKey struct #68500
-pkg crypto/tls, type EncryptedClientHelloKey struct, Config []uint8 #68500
-pkg crypto/tls, type EncryptedClientHelloKey struct, PrivateKey []uint8 #68500
-pkg crypto/tls, type EncryptedClientHelloKey struct, SendAsRetry bool #68500
-pkg crypto/x509, const NoValidChains = 10 #68484
-pkg crypto/x509, const NoValidChains InvalidReason #68484
-pkg crypto/x509, method (OID) AppendBinary([]uint8) ([]uint8, error) #62384
-pkg crypto/x509, method (OID) AppendText([]uint8) ([]uint8, error) #62384
-pkg crypto/x509, type Certificate struct, InhibitAnyPolicy int #68484
-pkg crypto/x509, type Certificate struct, InhibitAnyPolicyZero bool #68484
-pkg crypto/x509, type Certificate struct, InhibitPolicyMapping int #68484
-pkg crypto/x509, type Certificate struct, InhibitPolicyMappingZero bool #68484
-pkg crypto/x509, type Certificate struct, PolicyMappings []PolicyMapping #68484
-pkg crypto/x509, type Certificate struct, RequireExplicitPolicy int #68484
-pkg crypto/x509, type Certificate struct, RequireExplicitPolicyZero bool #68484
-pkg crypto/x509, type PolicyMapping struct #68484
-pkg crypto/x509, type PolicyMapping struct, IssuerDomainPolicy OID #68484
-pkg crypto/x509, type PolicyMapping struct, SubjectDomainPolicy OID #68484
-pkg crypto/x509, type VerifyOptions struct, CertificatePolicies []OID #68484
-pkg debug/elf, const VER_FLG_BASE = 1 #63952
-pkg debug/elf, const VER_FLG_BASE DynamicVersionFlag #63952
-pkg debug/elf, const VER_FLG_INFO = 4 #63952
-pkg debug/elf, const VER_FLG_INFO DynamicVersionFlag #63952
-pkg debug/elf, const VER_FLG_WEAK = 2 #63952
-pkg debug/elf, const VER_FLG_WEAK DynamicVersionFlag #63952
-pkg debug/elf, method (*File) DynamicVersionNeeds() ([]DynamicVersionNeed, error) #63952
-pkg debug/elf, method (*File) DynamicVersions() ([]DynamicVersion, error) #63952
-pkg debug/elf, type DynamicVersion struct #63952
-pkg debug/elf, type DynamicVersion struct, Deps []string #63952
-pkg debug/elf, type DynamicVersion struct, Flags DynamicVersionFlag #63952
-pkg debug/elf, type DynamicVersion struct, Name string #63952
-pkg debug/elf, type DynamicVersion struct, Index uint16 #63952
-pkg debug/elf, type DynamicVersionDep struct #63952
-pkg debug/elf, type DynamicVersionDep struct, Dep string #63952
-pkg debug/elf, type DynamicVersionDep struct, Flags DynamicVersionFlag #63952
-pkg debug/elf, type DynamicVersionDep struct, Index uint16 #63952
-pkg debug/elf, type DynamicVersionFlag uint16 #63952
-pkg debug/elf, type DynamicVersionNeed struct #63952
-pkg debug/elf, type DynamicVersionNeed struct, Name string #63952
-pkg debug/elf, type DynamicVersionNeed struct, Needs []DynamicVersionDep #63952
-pkg debug/elf, type Symbol struct, HasVersion bool #63952
-pkg debug/elf, type Symbol struct, VersionIndex VersionIndex #63952
-pkg debug/elf, method (VersionIndex) Index() uint16 #63952
-pkg debug/elf, method (VersionIndex) IsHidden() bool #63952
-pkg debug/elf, type VersionIndex uint16 #63952
-pkg encoding, type BinaryAppender interface { AppendBinary } #62384
-pkg encoding, type BinaryAppender interface, AppendBinary([]uint8) ([]uint8, error) #62384
-pkg encoding, type TextAppender interface { AppendText } #62384
-pkg encoding, type TextAppender interface, AppendText([]uint8) ([]uint8, error) #62384
-pkg go/types, method (*Interface) EmbeddedTypes() iter.Seq[Type] #66626
-pkg go/types, method (*Interface) ExplicitMethods() iter.Seq[*Func] #66626
-pkg go/types, method (*Interface) Methods() iter.Seq[*Func] #66626
-pkg go/types, method (*MethodSet) Methods() iter.Seq[*Selection] #66626
-pkg go/types, method (*Named) Methods() iter.Seq[*Func] #66626
-pkg go/types, method (*Scope) Children() iter.Seq[*Scope] #66626
-pkg go/types, method (*Struct) Fields() iter.Seq[*Var] #66626
-pkg go/types, method (*Tuple) Variables() iter.Seq[*Var] #66626
-pkg go/types, method (*TypeList) Types() iter.Seq[Type] #66626
-pkg go/types, method (*TypeParamList) TypeParams() iter.Seq[*TypeParam] #66626
-pkg go/types, method (*Union) Terms() iter.Seq[*Term] #66626
-pkg hash/maphash, func Comparable[$0 comparable](Seed, $0) uint64 #54670
-pkg hash/maphash, func WriteComparable[$0 comparable](*Hash, $0) #54670
-pkg log/slog, method (*LevelVar) AppendText([]uint8) ([]uint8, error) #62384
-pkg log/slog, method (Level) AppendText([]uint8) ([]uint8, error) #62384
-pkg log/slog, var DiscardHandler Handler #62005
-pkg math/big, method (*Float) AppendText([]uint8) ([]uint8, error) #62384
-pkg math/big, method (*Int) AppendText([]uint8) ([]uint8, error) #62384
-pkg math/big, method (*Rat) AppendText([]uint8) ([]uint8, error) #62384
-pkg math/rand/v2, method (*ChaCha8) AppendBinary([]uint8) ([]uint8, error) #62384
-pkg math/rand/v2, method (*PCG) AppendBinary([]uint8) ([]uint8, error) #62384
-pkg net, method (IP) AppendText([]uint8) ([]uint8, error) #62384
-pkg net/http, method (*Protocols) SetHTTP1(bool) #67814
-pkg net/http, method (*Protocols) SetHTTP2(bool) #67814
-pkg net/http, method (*Protocols) SetUnencryptedHTTP2(bool) #67816
-pkg net/http, method (Protocols) HTTP1() bool #67814
-pkg net/http, method (Protocols) HTTP2() bool #67814
-pkg net/http, method (Protocols) String() string #67814
-pkg net/http, method (Protocols) UnencryptedHTTP2() bool #67816
-pkg net/http, type HTTP2Config struct #67813
-pkg net/http, type HTTP2Config struct, CountError func(string) #67813
-pkg net/http, type HTTP2Config struct, MaxConcurrentStreams int #67813
-pkg net/http, type HTTP2Config struct, MaxDecoderHeaderTableSize int #67813
-pkg net/http, type HTTP2Config struct, MaxEncoderHeaderTableSize int #67813
-pkg net/http, type HTTP2Config struct, MaxReadFrameSize int #67813
-pkg net/http, type HTTP2Config struct, MaxReceiveBufferPerConnection int #67813
-pkg net/http, type HTTP2Config struct, MaxReceiveBufferPerStream int #67813
-pkg net/http, type HTTP2Config struct, PermitProhibitedCipherSuites bool #67813
-pkg net/http, type HTTP2Config struct, PingTimeout time.Duration #67813
-pkg net/http, type HTTP2Config struct, SendPingTimeout time.Duration #67813
-pkg net/http, type HTTP2Config struct, WriteByteTimeout time.Duration #67813
-pkg net/http, type Protocols struct #67814
-pkg net/http, type Server struct, HTTP2 *HTTP2Config #67813
-pkg net/http, type Server struct, Protocols *Protocols #67814
-pkg net/http, type Transport struct, HTTP2 *HTTP2Config #67813
-pkg net/http, type Transport struct, Protocols *Protocols #67814
-pkg net/netip, method (Addr) AppendBinary([]uint8) ([]uint8, error) #62384
-pkg net/netip, method (Addr) AppendText([]uint8) ([]uint8, error) #62384
-pkg net/netip, method (AddrPort) AppendBinary([]uint8) ([]uint8, error) #62384
-pkg net/netip, method (AddrPort) AppendText([]uint8) ([]uint8, error) #62384
-pkg net/netip, method (Prefix) AppendBinary([]uint8) ([]uint8, error) #62384
-pkg net/netip, method (Prefix) AppendText([]uint8) ([]uint8, error) #62384
-pkg net/url, method (*URL) AppendBinary([]uint8) ([]uint8, error) #62384
-pkg os, func OpenInRoot(string, string) (*File, error) #67002
-pkg os, func OpenRoot(string) (*Root, error) #67002
-pkg os, method (*Root) Close() error #67002
-pkg os, method (*Root) Create(string) (*File, error) #67002
-pkg os, method (*Root) FS() fs.FS #67002
-pkg os, method (*Root) Lstat(string) (fs.FileInfo, error) #67002
-pkg os, method (*Root) Mkdir(string, fs.FileMode) error #67002
-pkg os, method (*Root) Name() string #67002
-pkg os, method (*Root) Open(string) (*File, error) #67002
-pkg os, method (*Root) OpenFile(string, int, fs.FileMode) (*File, error) #67002
-pkg os, method (*Root) OpenRoot(string) (*Root, error) #67002
-pkg os, method (*Root) Remove(string) error #67002
-pkg os, method (*Root) Stat(string) (fs.FileInfo, error) #67002
-pkg os, type Root struct #67002
-pkg regexp, method (*Regexp) AppendText([]uint8) ([]uint8, error) #62384
-pkg runtime, func AddCleanup[$0 interface{}, $1 interface{}](*$0, func($1), $1) Cleanup #67535
-pkg runtime, func GOROOT //deprecated #51473
-pkg runtime, method (Cleanup) Stop() #67535
-pkg runtime, type Cleanup struct #67535
-pkg strings, func FieldsFuncSeq(string, func(int32) bool) iter.Seq[string] #61901
-pkg strings, func FieldsSeq(string) iter.Seq[string] #61901
-pkg strings, func Lines(string) iter.Seq[string] #61901
-pkg strings, func SplitAfterSeq(string, string) iter.Seq[string] #61901
-pkg strings, func SplitSeq(string, string) iter.Seq[string] #61901
-pkg testing, method (*B) Chdir(string) #62516
-pkg testing, method (*B) Context() context.Context #36532
-pkg testing, method (*B) Loop() bool #61515
-pkg testing, method (*F) Chdir(string) #62516
-pkg testing, method (*F) Context() context.Context #36532
-pkg testing, method (*T) Chdir(string) #62516
-pkg testing, method (*T) Context() context.Context #36532
-pkg testing, type TB interface, Chdir(string) #62516
-pkg testing, type TB interface, Context() context.Context #36532
-pkg time, method (Time) AppendBinary([]uint8) ([]uint8, error) #62384
-pkg time, method (Time) AppendText([]uint8) ([]uint8, error) #62384
-pkg weak, func Make[$0 interface{}](*$0) Pointer[$0] #67552
-pkg weak, method (Pointer[$0]) Value() *$0 #67552
-pkg weak, type Pointer[$0 interface{}] struct #67552

api/next/46771.txt

@@ -1 +0,0 @@
-pkg mime/multipart, func FileContentDisposition(string, string) string #46771

api/next/49580.txt

@@ -1,8 +0,0 @@
-pkg io/fs, func Lstat(FS, string) (FileInfo, error) #49580
-pkg io/fs, func ReadLink(FS, string) (string, error) #49580
-pkg io/fs, type ReadLinkFS interface { Lstat, Open, ReadLink } #49580
-pkg io/fs, type ReadLinkFS interface, Lstat(string) (FileInfo, error) #49580
-pkg io/fs, type ReadLinkFS interface, Open(string) (File, error) #49580
-pkg io/fs, type ReadLinkFS interface, ReadLink(string) (string, error) #49580
-pkg testing/fstest, method (MapFS) Lstat(string) (fs.FileInfo, error) #49580
-pkg testing/fstest, method (MapFS) ReadLink(string) (string, error) #49580

api/next/63796.txt

@@ -1 +0,0 @@
-pkg sync, method (*WaitGroup) Go(func()) #63769

api/next/67002.txt

@@ -1,8 +0,0 @@
-pkg os, method (*Root) Chmod(string, fs.FileMode) error #67002
-pkg os, method (*Root) Chown(string, int, int) error #67002
-pkg os, method (*Root) Chtimes(string, time.Time, time.Time) error #67002
-pkg os, method (*Root) Lchown(string, int, int) error #67002
-pkg os, method (*Root) Link(string, string) error #67002
-pkg os, method (*Root) Readlink(string) (string, error) #67002
-pkg os, method (*Root) Rename(string, string) error #67002
-pkg os, method (*Root) Symlink(string, string) error #67002

api/next/67516.txt

@@ -1 +0,0 @@
-pkg crypto/tls, type ConnectionState struct, CurveID CurveID #67516

api/next/70250.txt

@@ -1,17 +0,0 @@
-pkg go/types, const FieldVar = 6 #70250
-pkg go/types, const FieldVar VarKind #70250
-pkg go/types, const LocalVar = 2 #70250
-pkg go/types, const LocalVar VarKind #70250
-pkg go/types, const PackageVar = 1 #70250
-pkg go/types, const PackageVar VarKind #70250
-pkg go/types, const ParamVar = 4 #70250
-pkg go/types, const ParamVar VarKind #70250
-pkg go/types, const RecvVar = 3 #70250
-pkg go/types, const RecvVar VarKind #70250
-pkg go/types, const ResultVar = 5 #70250
-pkg go/types, const ResultVar VarKind #70250
-pkg go/types, func LookupSelection(Type, bool, *Package, string) (Selection, bool) #70737
-pkg go/types, method (*Var) Kind() VarKind #70250
-pkg go/types, method (*Var) SetKind(VarKind) #70250
-pkg go/types, method (VarKind) String() string #70250
-pkg go/types, type VarKind uint8 #70250

api/next/70280.txt

@@ -1 +0,0 @@
-pkg log/slog, method (Record) Source() *Source #70280

api/next/70780.txt

@@ -1,3 +0,0 @@
-pkg unicode, var CategoryAliases map[string]string #70780
-pkg unicode, var Cn *RangeTable #70780
-pkg unicode, var LC *RangeTable #70780

api/next/71122.txt

@@ -1 +0,0 @@
-pkg go/parser, func ParseDir //deprecated #71122

api/next/72843.txt

@@ -1,4 +0,0 @@
-pkg debug/elf, const PT_RISCV_ATTRIBUTES = 1879048195 #72843
-pkg debug/elf, const PT_RISCV_ATTRIBUTES ProgType #72843
-pkg debug/elf, const SHT_RISCV_ATTRIBUTES = 1879048195 #72843
-pkg debug/elf, const SHT_RISCV_ATTRIBUTES SectionType #72843

codereview.cfg

@@ -1 +1,2 @@
-branch: master
+branch: release-branch.go1.23
+parent-branch: master

doc/README.md

@@ -70,6 +70,6 @@ To begin the next release development cycle, populate the contents of `next`
 with those of `initial`. From the repo root:
 
     > cd doc
-    > cp -R initial/ next
+    > cp -r initial/* next
 
 Then edit `next/1-intro.md` to refer to the next version.

doc/go_mem.html

@@ -82,7 +82,7 @@ while still insisting that races are errors and that tools can diagnose and repo
 <p>
 The following formal definition of Go's memory model closely follows
 the approach presented by Hans-J. Boehm and Sarita V. Adve in
-“<a href="https://dl.acm.org/doi/10.1145/1375581.1375591">Foundations of the C++ Concurrency Memory Model</a>”,
+“<a href="https://www.hpl.hp.com/techreports/2008/HPL-2008-56.pdf">Foundations of the C++ Concurrency Memory Model</a>”,
 published in PLDI 2008.
 The definition of data-race-free programs and the guarantee of sequential consistency
 for race-free programs are equivalent to the ones in that work.
@@ -453,7 +453,7 @@ crash, or do something else.)
 </p>
 
 <p class="rule">
-The <i>k</i>th receive from a channel with capacity <i>C</i> is synchronized before the completion of the <i>k</i>+<i>C</i>th send on that channel.
+The <i>k</i>th receive on a channel with capacity <i>C</i> is synchronized before the completion of the <i>k</i>+<i>C</i>th send from that channel completes.
 </p>
 
 <p>

doc/go_spec.html

@@ -1,6 +1,6 @@
 <!--{
 	"Title": "The Go Programming Language Specification",
-	"Subtitle": "Language version go1.25 (Feb 25, 2025)",
+	"Subtitle": "Language version go1.23 (June 13, 2024)",
 	"Path": "/ref/spec"
 }-->
 
@@ -8,6 +8,8 @@
 
 <p>
 This is the reference manual for the Go programming language.
+The pre-Go1.18 version, without generics, can be found
+<a href="/doc/go1.17_spec.html">here</a>.
 For more information and other documents, see <a href="/">go.dev</a>.
 </p>
 
@@ -796,6 +798,7 @@ If a variable has not yet been assigned a value, its value is the
 <a href="#The_zero_value">zero value</a> for its type.
 </p>
 
+
 <h2 id="Types">Types</h2>
 
 <p>
@@ -1083,7 +1086,7 @@ A field declared with a type but no explicit field name is called an <i>embedded
 An embedded field must be specified as
 a type name <code>T</code> or as a pointer to a non-interface type name <code>*T</code>,
 and <code>T</code> itself may not be
-a pointer type or type parameter. The unqualified type name acts as the field name.
+a pointer type. The unqualified type name acts as the field name.
 </p>
 
 <pre>
@@ -1124,7 +1127,7 @@ of a struct except that they cannot be used as field names in
 </p>
 
 <p>
-Given a struct type <code>S</code> and a type name
+Given a struct type <code>S</code> and a <a href="#Types">named type</a>
 <code>T</code>, promoted methods are included in the method set of the struct as follows:
 </p>
 <ul>
@@ -1197,7 +1200,7 @@ type (
 <p>
 A pointer type denotes the set of all pointers to <a href="#Variables">variables</a> of a given
 type, called the <i>base type</i> of the pointer.
-The <a href="#Representation_of_values">value</a> of an uninitialized pointer is <code>nil</code>.
+The value of an uninitialized pointer is <code>nil</code>.
 </p>
 
 <pre class="ebnf">
@@ -1213,9 +1216,9 @@ BaseType    = Type .
 <h3 id="Function_types">Function types</h3>
 
 <p>
-A function type denotes the set of all functions with the same parameter and result types.
-The <a href="#Representation_of_values">value</a> of an uninitialized variable of function
-type is <code>nil</code>.
+A function type denotes the set of all functions with the same parameter
+and result types. The value of an uninitialized variable of function type
+is <code>nil</code>.
 </p>
 
 <pre class="ebnf">
@@ -1264,8 +1267,7 @@ An interface type defines a <i>type set</i>.
 A variable of interface type can store a value of any type that is in the type
 set of the interface. Such a type is said to
 <a href="#Implementing_an_interface">implement the interface</a>.
-The <a href="#Representation_of_values">value</a> of an uninitialized variable of
-interface type is <code>nil</code>.
+The value of an uninitialized variable of interface type is <code>nil</code>.
 </p>
 
 <pre class="ebnf">
@@ -1628,7 +1630,7 @@ implements the interface.
 A map is an unordered group of elements of one type, called the
 element type, indexed by a set of unique <i>keys</i> of another type,
 called the key type.
-The <a href="#Representation_of_values">value</a> of an uninitialized map is <code>nil</code>.
+The value of an uninitialized map is <code>nil</code>.
 </p>
 
 <pre class="ebnf">
@@ -1691,7 +1693,7 @@ to communicate by
 <a href="#Send_statements">sending</a> and
 <a href="#Receive_operator">receiving</a>
 values of a specified element type.
-The <a href="#Representation_of_values">value</a> of an uninitialized channel is <code>nil</code>.
+The value of an uninitialized channel is <code>nil</code>.
 </p>
 
 <pre class="ebnf">
@@ -1770,57 +1772,6 @@ received in the order sent.
 
 <h2 id="Properties_of_types_and_values">Properties of types and values</h2>
 
-<h3 id="Representation_of_values">Representation of values</h3>
-
-<p>
-Values of predeclared types (see below for the interfaces <code>any</code>
-and <code>error</code>), arrays, and structs are self-contained:
-Each such value contains a complete copy of all its data,
-and <a href="#Variables">variables</a> of such types store the entire value.
-For instance, an array variable provides the storage (the variables)
-for all elements of the array.
-The respective <a href="#The_zero_value">zero values</a> are specific to the
-value's types; they are never <code>nil</code>.
-</p>
-
-<p>
-Non-nil pointer, function, slice, map, and channel values contain references
-to underlying data which may be shared by multiple values:
-</p>
-
-<ul>
-<li>
-	A pointer value is a reference to the variable holding
-	the pointer base type value.
-</li>
-<li>
-	A function value contains references to the (possibly
-	<a href="#Function_literals">anonymous</a>) function
-	and enclosed variables.
-</li>
-<li>
-	A slice value contains the slice length, capacity, and
-	a reference to its <a href="#Slice_types">underlying array</a>.
-</li>
-<li>
-	A map or channel value is a reference to the implementation-specific
-	data structure of the map or channel.
-</li>
-</ul>
-
-<p>
-An interface value may be self-contained or contain references to underlying data
-depending on the interface's <a href="#Variables">dynamic type</a>.
-The predeclared identifier <code>nil</code> is the zero value for types whose values
-can contain references.
-</p>
-
-<p>
-When multiple values share underlying data, changing one value may change another.
-For instance, changing an element of a <a href="#Slice_types">slice</a> will change
-that element in the underlying array for all slices that share the array.
-</p>
-
 <h3 id="Underlying_types">Underlying types</h3>
 
 <p>
@@ -1856,10 +1807,110 @@ The underlying type of <code>[]B1</code>, <code>B3</code>, and <code>B4</code> i
 The underlying type of <code>P</code> is <code>interface{}</code>.
 </p>
 
+<h3 id="Core_types">Core types</h3>
+
+<p>
+Each non-interface type <code>T</code> has a <i>core type</i>, which is the same as the
+<a href="#Underlying_types">underlying type</a> of <code>T</code>.
+</p>
+
+<p>
+An interface <code>T</code> has a core type if one of the following
+conditions is satisfied:
+</p>
+
+<ol>
+<li>
+There is a single type <code>U</code> which is the <a href="#Underlying_types">underlying type</a>
+of all types in the <a href="#Interface_types">type set</a> of <code>T</code>; or
+</li>
+<li>
+the type set of <code>T</code> contains only <a href="#Channel_types">channel types</a>
+with identical element type <code>E</code>, and all directional channels have the same
+direction.
+</li>
+</ol>
+
+<p>
+No other interfaces have a core type.
+</p>
+
+<p>
+The core type of an interface is, depending on the condition that is satisfied, either:
+</p>
+
+<ol>
+<li>
+the type <code>U</code>; or
+</li>
+<li>
+the type <code>chan E</code> if <code>T</code> contains only bidirectional
+channels, or the type <code>chan&lt;- E</code> or <code>&lt;-chan E</code>
+depending on the direction of the directional channels present.
+</li>
+</ol>
+
+<p>
+By definition, a core type is never a <a href="#Type_definitions">defined type</a>,
+<a href="#Type_parameter_declarations">type parameter</a>, or
+<a href="#Interface_types">interface type</a>.
+</p>
+
+<p>
+Examples of interfaces with core types:
+</p>
+
+<pre>
+type Celsius float32
+type Kelvin  float32
+
+interface{ int }                          // int
+interface{ Celsius|Kelvin }               // float32
+interface{ ~chan int }                    // chan int
+interface{ ~chan int|~chan&lt;- int }        // chan&lt;- int
+interface{ ~[]*data; String() string }    // []*data
+</pre>
+
+<p>
+Examples of interfaces without core types:
+</p>
+
+<pre>
+interface{}                               // no single underlying type
+interface{ Celsius|float64 }              // no single underlying type
+interface{ chan int | chan&lt;- string }     // channels have different element types
+interface{ &lt;-chan int | chan&lt;- int }      // directional channels have different directions
+</pre>
+
+<p>
+Some operations (<a href="#Slice_expressions">slice expressions</a>,
+<a href="#Appending_and_copying_slices"><code>append</code> and <code>copy</code></a>)
+rely on a slightly more loose form of core types which accept byte slices and strings.
+Specifically, if there are exactly two types, <code>[]byte</code> and <code>string</code>,
+which are the underlying types of all types in the type set of interface <code>T</code>,
+the core type of <code>T</code> is called <code>bytestring</code>.
+</p>
+
+<p>
+Examples of interfaces with <code>bytestring</code> core types:
+</p>
+
+<pre>
+interface{ int }                          // int (same as ordinary core type)
+interface{ []byte | string }              // bytestring
+interface{ ~[]byte | myString }           // bytestring
+</pre>
+
+<p>
+Note that <code>bytestring</code> is not a real type; it cannot be used to declare
+variables or compose other types. It exists solely to describe the behavior of some
+operations that read from a sequence of bytes, which may be a byte slice or a string.
+</p>
+
 <h3 id="Type_identity">Type identity</h3>
 
 <p>
-Two types are either <i>identical</i> ("the same") or <i>different</i>.
+Two types are either <i>identical</i> or <i>different</i>.
 </p>
 
 <p>
@@ -1876,8 +1927,8 @@ components have identical types. In detail:
 	<li>Two slice types are identical if they have identical element types.</li>
 
 	<li>Two struct types are identical if they have the same sequence of fields,
-	    and if corresponding pairs of fields have the same names, identical types,
-	    and identical tags, and are either both embedded or both not embedded.
+	    and if corresponding fields have the same names, and identical types,
+	    and identical tags.
 	    <a href="#Exported_identifiers">Non-exported</a> field names from different
 	    packages are always different.</li>
 
@@ -2460,12 +2511,12 @@ An alias declaration binds an identifier to the given type
 </p>
 
 <pre class="ebnf">
-AliasDecl = identifier [ TypeParameters ] "=" Type .
+AliasDecl = identifier "=" Type .
 </pre>
 
 <p>
 Within the <a href="#Declarations_and_scope">scope</a> of
-the identifier, it serves as an <i>alias</i> for the given type.
+the identifier, it serves as an <i>alias</i> for the type.
 </p>
 
 <pre>
@@ -2475,24 +2526,6 @@ type (
 )
 </pre>
 
-<p>
-If the alias declaration specifies <a href="#Type_parameter_declarations">type parameters</a>
-[<a href="#Go_1.24">Go 1.24</a>], the type name denotes a <i>generic alias</i>.
-Generic aliases must be <a href="#Instantiations">instantiated</a> when they
-are used.
-</p>
-
-<pre>
-type set[P comparable] = map[P]bool
-</pre>
-
-<p>
-In an alias declaration the given type cannot be a type parameter.
-</p>
-
-<pre>
-type A[P any] = P    // illegal: P is a type parameter
-</pre>
 
 <h4 id="Type_definitions">Type definitions</h4>
 
@@ -2768,7 +2801,7 @@ values or variables, or components of other, non-interface types.
 
 <p>
 A type argument <code>T</code><i> satisfies</i> a type constraint <code>C</code>
-if <code>T</code> is an element of the type set defined by <code>C</code>; in other words,
+if <code>T</code> is an element of the type set defined by <code>C</code>; i.e.,
 if <code>T</code> <a href="#Implementing_an_interface">implements</a> <code>C</code>.
 As an exception, a <a href="#Comparison_operators">strictly comparable</a>
 type constraint may also be satisfied by a <a href="#Comparison_operators">comparable</a>
@@ -2848,7 +2881,7 @@ initialization value in the assignment.
 If that value is an untyped constant, it is first implicitly
 <a href="#Conversions">converted</a> to its <a href="#Constants">default type</a>;
 if it is an untyped boolean value, it is first implicitly converted to type <code>bool</code>.
-The predeclared identifier <code>nil</code> cannot be used to initialize a variable
+The predeclared value <code>nil</code> cannot be used to initialize a variable
 with no explicit type.
 </p>
 
@@ -3042,7 +3075,7 @@ to the base type <code>Point</code>.
 </p>
 
 <p>
-If the receiver base type is a <a href="#Type_definitions">generic type</a>, the
+If the receiver base type is a <a href="#Type_declarations">generic type</a>, the
 receiver specification must declare corresponding type parameters for the method
 to use. This makes the receiver type parameters available to the method.
 Syntactically, this type parameter declaration looks like an
@@ -3066,22 +3099,6 @@ func (p Pair[A, B]) Swap() Pair[B, A]  { … }  // receiver declares A, B
 func (p Pair[First, _]) First() First  { … }  // receiver declares First, corresponds to A in Pair
 </pre>
 
-<p>
-If the receiver type is denoted by (a pointer to) an <a href="#Alias_declarations">alias</a>,
-the alias must not be generic and it must not denote an instantiated generic type, neither
-directly nor indirectly via another alias, and irrespective of pointer indirections.
-</p>
-
-<pre>
-type GPoint[P any] = Point
-type HPoint        = *GPoint[int]
-type IPair         = Pair[int, int]
-
-func (*GPoint[P]) Draw(P)   { … }  // illegal: alias must not be generic
-func (HPoint) Draw(P)       { … }  // illegal: alias must not denote instantiated type GPoint[int]
-func (*IPair) Second() int  { … }  // illegal: alias must not denote instantiated type Pair[int, int]
-</pre>
-
 <h2 id="Expressions">Expressions</h2>
 
 <p>
@@ -3153,8 +3170,7 @@ math.Sin // denotes the Sin function in package math
 <h3 id="Composite_literals">Composite literals</h3>
 
 <p>
-Composite literals construct new values for structs, arrays, slices, and maps
-each time they are evaluated.
+Composite literals construct new composite values each time they are evaluated.
 They consist of the type of the literal followed by a brace-bound list of elements.
 Each element may optionally be preceded by a corresponding key.
 </p>
@@ -3172,14 +3188,10 @@ Element      = Expression | LiteralValue .
 </pre>
 
 <p>
-Unless the LiteralType is a type parameter,
-its <a href="#Underlying_types">underlying type
+The LiteralType's <a href="#Core_types">core type</a> <code>T</code>
 must be a struct, array, slice, or map type
 (the syntax enforces this constraint except when the type is given
 as a TypeName).
-If the LiteralType is a type parameter, all types in its type set
-must have the same underlying type which must be
-a valid composite literal type.
 The types of the elements and keys must be <a href="#Assignability">assignable</a>
 to the respective field, element, and key types of type <code>T</code>;
 there is no additional conversion.
@@ -3364,6 +3376,7 @@ noteFrequency := map[string]float32{
 }
 </pre>
 
+
 <h3 id="Function_literals">Function literals</h3>
 
 <p>
@@ -3403,7 +3416,8 @@ Primary expressions are the operands for unary and binary expressions.
 </p>
 
 <pre class="ebnf">
-PrimaryExpr   = Operand |
+PrimaryExpr =
+	Operand |
 	Conversion |
 	MethodExpr |
 	PrimaryExpr Selector |
@@ -3836,12 +3850,11 @@ The following rules apply:
 </p>
 
 <p>
-If <code>a</code> is neither a map nor a <a href="#Type_parameter_declarations">type parameter</a>:
+If <code>a</code> is neither a map nor a type parameter:
 </p>
 <ul>
-	<li>the index <code>x</code> must be an untyped constant, or its type must be
-	    an <a href="#Numeric_types">integer</a> or a type parameter whose type set
-	    contains only integer types</li>
+	<li>the index <code>x</code> must be an untyped constant or its
+	    <a href="#Core_types">core type</a> must be an <a href="#Numeric_types">integer</a></li>
 	<li>a constant index must be non-negative and
 	    <a href="#Representability">representable</a> by a value of type <code>int</code></li>
 	<li>a constant index that is untyped is given type <code>int</code></li>
@@ -3955,26 +3968,14 @@ Assigning to an element of a <code>nil</code> map causes a
 
 <p>
 Slice expressions construct a substring or slice from a string, array, pointer
-to array, or slice operand.
-There are two variants: a simple form that specifies a low
+to array, or slice. There are two variants: a simple form that specifies a low
 and high bound, and a full form that also specifies a bound on the capacity.
 </p>
 
-<p>
-If the operand type is a <a href="#Type_parameter_declarations">type parameter</a>,
-unless its type set contains string types,
-all types in the type set must have the same underlying type, and the slice expression
-must be valid for an operand of that type.
-If the type set contains string types it may also contain byte slices with underlying
-type <code>[]byte</code>.
-In this case, the slice expression must be valid for an operand of <code>string</code>
-type.
-</p>
-
 <h4>Simple slice expressions</h4>
 
 <p>
-For a string, array, pointer to array, or slice <code>a</code>, the primary expression
+The primary expression
 </p>
 
 <pre>
@@ -3982,7 +3983,9 @@ a[low : high]
 </pre>
 
 <p>
-constructs a substring or slice.
+constructs a substring or slice. The <a href="#Core_types">core type</a> of
+<code>a</code> must be a string, array, pointer to array, slice, or a
+<a href="#Core_types"><code>bytestring</code></a>.
 The <i>indices</i> <code>low</code> and
 <code>high</code> select which elements of operand <code>a</code> appear
 in the result. The result has indices starting at 0 and length equal to
@@ -4062,7 +4065,7 @@ s3 := s[:0]    // s3 == nil
 <h4>Full slice expressions</h4>
 
 <p>
-For an array, pointer to array, or slice <code>a</code> (but not a string), the primary expression
+The primary expression
 </p>
 
 <pre>
@@ -4073,6 +4076,8 @@ a[low : high : max]
 constructs a slice of the same type, and with the same length and elements as the simple slice
 expression <code>a[low : high]</code>. Additionally, it controls the resulting slice's capacity
 by setting it to <code>max - low</code>. Only the first index may be omitted; it defaults to 0.
+The <a href="#Core_types">core type</a> of <code>a</code> must be an array, pointer to array,
+or slice (but not a string).
 After slicing the array <code>a</code>
 </p>
 
@@ -4178,8 +4183,8 @@ No <a href="#Run_time_panics">run-time panic</a> occurs in this case.
 <h3 id="Calls">Calls</h3>
 
 <p>
-Given an expression <code>f</code> of <a href="#Function_types">function type</a>
-<code>F</code>,
+Given an expression <code>f</code> with a <a href="#Core_types">core type</a>
+<code>F</code> of <a href="#Function_types">function type</a>,
 </p>
 
 <pre>
@@ -4191,7 +4196,8 @@ calls <code>f</code> with arguments <code>a1, a2, … an</code>.
 Except for one special case, arguments must be single-valued expressions
 <a href="#Assignability">assignable</a> to the parameter types of
 <code>F</code> and are evaluated before the function is called.
-The type of the expression is the result type of <code>F</code>.
+The type of the expression is the result type
+of <code>F</code>.
 A method invocation is similar but the method itself
 is specified as a selector upon a value of the receiver type for
 the method.
@@ -4209,23 +4215,12 @@ If <code>f</code> denotes a generic function, it must be
 or used as a function value.
 </p>
 
-<p>
-If the type of <code>f</code> is a <a href="#Type_parameter_declarations">type parameter</a>,
-all types in its type set must have the same underlying type, which must be a function type,
-and the function call must be valid for that type.
-</p>
-
 <p>
 In a function call, the function value and arguments are evaluated in
 <a href="#Order_of_evaluation">the usual order</a>.
-After they are evaluated, new storage is allocated for the function's
-<a href="#Variables">variables</a>, which includes its parameters
-and results.
-Then, the arguments of the call are <i>passed</i> to the function,
-which means that they are <a href="#Assignment_statements">assigned</a>
-to their corresponding function parameters,
+After they are evaluated, the parameters of the call are passed by value to the function
 and the called function begins execution.
-The return parameters of the function are passed
+The return parameters of the function are passed by value
 back to the caller when the function returns.
 </p>
 
@@ -4239,9 +4234,9 @@ As a special case, if the return values of a function or method
 <code>g</code> are equal in number and individually
 assignable to the parameters of another function or method
 <code>f</code>, then the call <code>f(g(<i>parameters_of_g</i>))</code>
-will invoke <code>f</code> after passing the return values of
-<code>g</code> to the parameters of <code>f</code> in order.
-The call of <code>f</code> must contain no parameters other than the call of <code>g</code>,
+will invoke <code>f</code> after binding the return values of
+<code>g</code> to the parameters of <code>f</code> in order.  The call
+of <code>f</code> must contain no parameters other than the call of <code>g</code>,
 and <code>g</code> must have at least one return value.
 If <code>f</code> has a final <code>...</code> parameter, it is
 assigned the return values of <code>g</code> that remain after
@@ -4287,7 +4282,7 @@ If <code>f</code> is <a href="#Function_types">variadic</a> with a final
 parameter <code>p</code> of type <code>...T</code>, then within <code>f</code>
 the type of <code>p</code> is equivalent to type <code>[]T</code>.
 If <code>f</code> is invoked with no actual arguments for <code>p</code>,
-the value <a href="#Calls">passed</a> to <code>p</code> is <code>nil</code>.
+the value passed to <code>p</code> is <code>nil</code>.
 Otherwise, the value passed is a new slice
 of type <code>[]T</code> with a new underlying array whose successive elements
 are the actual arguments, which all must be <a href="#Assignability">assignable</a>
@@ -4728,28 +4723,17 @@ more complicated:
 
 <ul>
 <li>
-	If all types in <code>C</code>'s type set have the same
-	underlying type <code>U</code>,
+	If <code>C</code> has a <a href="#Core_types">core type</a>
+	<code>core(C)</code>
 	and <code>P</code> has a known type argument <code>A</code>,
-	<code>U</code> and <code>A</code> must unify loosely.
-</li>
-<li>
-	Similarly, if all types in <code>C</code>'s type set are
-	channel types with the same element type and non-conflicting
-	channel directions,
-	and <code>P</code> has a known type argument <code>A</code>,
-	the most restrictive channel type in <code>C</code>'s type
-	set and <code>A</code> must unify loosely.
-</li>
-<li>
+	<code>core(C)</code> and <code>A</code> must unify loosely.
 	If <code>P</code> does not have a known type argument
 	and <code>C</code> contains exactly one type term <code>T</code>
 	that is not an underlying (tilde) type, unification adds the
 	mapping <code>P ➞ T</code> to the map.
 </li>
 <li>
-	If <code>C</code> does not have a type <code>U</code>
-	as described above
+	If <code>C</code> does not have a core type
 	and <code>P</code> has a known type argument <code>A</code>,
 	<code>A</code> must have all methods of <code>C</code>, if any,
 	and corresponding method types must unify exactly.
@@ -5300,10 +5284,10 @@ var x *int = nil
 <h3 id="Receive_operator">Receive operator</h3>
 
 <p>
-For an operand <code>ch</code> of <a href="#Channel_types">channel type</a>,
+For an operand <code>ch</code> whose <a href="#Core_types">core type</a> is a
+<a href="#Channel_types">channel</a>,
 the value of the receive operation <code>&lt;-ch</code> is the value received
-from the channel <code>ch</code>.
-The channel direction must permit receive operations,
+from the channel <code>ch</code>. The channel direction must permit receive operations,
 and the type of the receive operation is the element type of the channel.
 The expression blocks until a value is available.
 Receiving from a <code>nil</code> channel blocks forever.
@@ -5319,12 +5303,6 @@ f(&lt;-ch)
 &lt;-strobe  // wait until clock pulse and discard received value
 </pre>
 
-<p>
-If the operand type is a <a href="#Type_parameter_declarations">type parameter</a>,
-all types in its type set must be channel types that permit receive operations, and
-they must all have the same element type, which is the type of the receive operation.
-</p>
-
 <p>
 A receive expression used in an <a href="#Assignment_statements">assignment statement</a> or initialization of the special form
 </p>
@@ -5620,8 +5598,6 @@ myString([]myRune{0x1f30e})              // "\U0001f30e" == "🌎"
 <li>
 Converting a value of a string type to a slice of bytes type
 yields a non-nil slice whose successive elements are the bytes of the string.
-The <a href="#Length_and_capacity">capacity</a> of the resulting slice is
-implementation-specific and may be larger than the slice length.
 
 <pre>
 []byte("hellø")             // []byte{'h', 'e', 'l', 'l', '\xc3', '\xb8'}
@@ -5637,8 +5613,6 @@ bytes("hellø")              // []byte{'h', 'e', 'l', 'l', '\xc3', '\xb8'}
 <li>
 Converting a value of a string type to a slice of runes type
 yields a slice containing the individual Unicode code points of the string.
-The <a href="#Length_and_capacity">capacity</a> of the resulting slice is
-implementation-specific and may be larger than the slice length.
 
 <pre>
 []rune(myString("白鵬翔"))   // []rune{0x767d, 0x9d6c, 0x7fd4}
@@ -5840,7 +5814,7 @@ Otherwise, when evaluating the <a href="#Operands">operands</a> of an
 expression, assignment, or
 <a href="#Return_statements">return statement</a>,
 all function calls, method calls,
-<a href="#Receive_operator">receive operations</a>,
+<a href="#Receive operator">receive operations</a>,
 and <a href="#Logical_operators">binary logical operations</a>
 are evaluated in lexical left-to-right order.
 </p>
@@ -5908,7 +5882,8 @@ Statements control execution.
 </p>
 
 <pre class="ebnf">
-Statement  = Declaration | LabeledStmt | SimpleStmt |
+Statement =
+	Declaration | LabeledStmt | SimpleStmt |
 	GoStmt | ReturnStmt | BreakStmt | ContinueStmt | GotoStmt |
 	FallthroughStmt | Block | IfStmt | SwitchStmt | SelectStmt | ForStmt |
 	DeferStmt .
@@ -6060,7 +6035,8 @@ len("foo")  // illegal if len is the built-in function
 
 <p>
 A send statement sends a value on a channel.
-The channel expression must be of <a href="#Channel_types">channel type</a>,
+The channel expression's <a href="#Core_types">core type</a>
+must be a <a href="#Channel_types">channel</a>,
 the channel direction must permit send operations,
 and the type of the value to be sent must be <a href="#Assignability">assignable</a>
 to the channel's element type.
@@ -6084,13 +6060,6 @@ A send on a <code>nil</code> channel blocks forever.
 ch &lt;- 3  // send value 3 to channel ch
 </pre>
 
-<p>
-If the type of the channel expression is a
-<a href="#Type_parameter_declarations">type parameter</a>,
-all types in its type set must be channel types that permit send operations,
-they must all have the same element type,
-and the type of the value to be sent must be assignable to that element type.
-</p>
 
 <h3 id="IncDec_statements">IncDec statements</h3>
 
@@ -6258,26 +6227,6 @@ to the type of the operand to which it is assigned, with the following special c
 </li>
 </ol>
 
-<p>
-When a value is assigned to a variable, only the data that is stored in the variable
-is replaced. If the value contains a <a href="#Representation_of_values">reference</a>,
-the assignment copies the reference but does not make a copy of the referenced data
-(such as the underlying array of a slice).
-</p>
-
-<pre>
-var s1 = []int{1, 2, 3}
-var s2 = s1                    // s2 stores the slice descriptor of s1
-s1 = s1[:1]                    // s1's length is 1 but it still shares its underlying array with s2
-s2[0] = 42                     // setting s2[0] changes s1[0] as well
-fmt.Println(s1, s2)            // prints [42] [42 2 3]
-
-var m1 = make(map[string]int)
-var m2 = m1                    // m2 stores the map descriptor of m1
-m1["foo"] = 42                 // setting m1["foo"] changes m2["foo"] as well
-fmt.Println(m2["foo"])         // prints 42
-</pre>
-
 <h3 id="If_statements">If statements</h3>
 
 <p>
@@ -6683,7 +6632,8 @@ RangeClause = [ ExpressionList "=" | IdentifierList ":=" ] "range" Expression .
 
 <p>
 The expression on the right in the "range" clause is called the <i>range expression</i>,
-which may be an array, pointer to an array, slice, string, map, channel permitting
+its <a href="#Core_types">core type</a> must be
+an array, pointer to an array, slice, string, map, channel permitting
 <a href="#Receive_operator">receive operations</a>, an integer, or
 a function with specific signature (see below).
 As with an assignment, if present the operands on the left must be
@@ -6897,12 +6847,6 @@ for k, v := range t.Walk {
 }
 </pre>
 
-<p>
-If the type of the range expression is a <a href="#Type_parameter_declarations">type parameter</a>,
-all types in its type set must have the same underlying type and the range expression must be valid
-for that type, or, if the type set contains channel types, it must only contain channel types with
-identical element types, and all channel types must permit receive operations.
-</p>
 
 <h3 id="Go_statements">Go statements</h3>
 
@@ -7376,28 +7320,23 @@ by the arguments overlaps.
 
 <p>
 The <a href="#Function_types">variadic</a> function <code>append</code>
-appends zero or more values <code>x</code> to a slice <code>s</code> of
-type <code>S</code> and returns the resulting slice, also of type
-<code>S</code>.
+appends zero or more values <code>x</code> to a slice <code>s</code>
+and returns the resulting slice of the same type as <code>s</code>.
+The <a href="#Core_types">core type</a> of <code>s</code> must be a slice
+of type <code>[]E</code>.
 The values <code>x</code> are passed to a parameter of type <code>...E</code>
-where <code>E</code> is the element type of <code>S</code>
 and the respective <a href="#Passing_arguments_to_..._parameters">parameter
 passing rules</a> apply.
-As a special case, <code>append</code> also accepts a first argument assignable
-to type <code>[]byte</code> with a second argument of string type followed by
-<code>...</code>.
-This form appends the bytes of the string.
+As a special case, if the core type of <code>s</code> is <code>[]byte</code>,
+<code>append</code> also accepts a second argument with core type
+<a href="#Core_types"><code>bytestring</code></a> followed by <code>...</code>.
+This form appends the bytes of the byte slice or string.
 </p>
 
 <pre class="grammar">
-append(s S, x ...E) S  // E is the element type of S
+append(s S, x ...E) S  // core type of S is []E
 </pre>
 
-<p>
-If <code>S</code> is a <a href="#Type_parameter_declarations">type parameter</a>,
-all types in its type set must have the same underlying slice type <code>[]E</code>.
-</p>
-
 <p>
 If the capacity of <code>s</code> is not large enough to fit the additional
 values, <code>append</code> <a href="#Allocation">allocates</a> a new, sufficiently large underlying
@@ -7423,14 +7362,14 @@ b = append(b, "bar"...)            // append string contents      b is []byte{'b
 The function <code>copy</code> copies slice elements from
 a source <code>src</code> to a destination <code>dst</code> and returns the
 number of elements copied.
-Both arguments must have <a href="#Type_identity">identical</a> element type
-<code>E</code> and must be assignable to a slice of type <code>[]E</code>.
+The <a href="#Core_types">core types</a> of both arguments must be slices
+with <a href="#Type_identity">identical</a> element type.
 The number of elements copied is the minimum of
 <code>len(src)</code> and <code>len(dst)</code>.
-As a special case, <code>copy</code> also accepts a destination argument
-assignable to type <code>[]byte</code> with a source argument of a
-<code>string</code> type.
-This form copies the bytes from the string into the byte slice.
+As a special case, if the destination's core type is <code>[]byte</code>,
+<code>copy</code> also accepts a source argument with core type
+<a href="#Core_types"><code>bytestring</code></a>.
+This form copies the bytes from the byte slice or string into the byte slice.
 </p>
 
 <pre class="grammar">
@@ -7438,11 +7377,6 @@ copy(dst, src []T) int
 copy(dst []byte, src string) int
 </pre>
 
-<p>
-If the type of one or both arguments is a <a href="#Type_parameter_declarations">type parameter</a>,
-all types in their respective type sets must have the same underlying slice type <code>[]E</code>.
-</p>
-
 <p>
 Examples:
 </p>
@@ -7493,7 +7427,8 @@ If the map or slice is <code>nil</code>, <code>clear</code> is a no-op.
 <h3 id="Close">Close</h3>
 
 <p>
-For a channel <code>ch</code>, the built-in function <code>close(ch)</code>
+For an argument <code>ch</code> with a <a href="#Core_types">core type</a>
+that is a <a href="#Channel_types">channel</a>, the built-in function <code>close</code>
 records that no more values will be sent on the channel.
 It is an error if <code>ch</code> is a receive-only channel.
 Sending to or closing a closed channel causes a <a href="#Run_time_panics">run-time panic</a>.
@@ -7505,12 +7440,6 @@ The multi-valued <a href="#Receive_operator">receive operation</a>
 returns a received value along with an indication of whether the channel is closed.
 </p>
 
-<p>
-If the type of the argument to <code>close</code> is a
-<a href="#Type_parameter_declarations">type parameter</a>,
-all types in its type set must be channels with the same element type.
-It is an error if any of those channels is a receive-only channel.
-</p>
 
 <h3 id="Complex_numbers">Manipulating complex numbers</h3>
 
@@ -7680,15 +7609,16 @@ var z complex128
 
 <p>
 The built-in function <code>make</code> takes a type <code>T</code>,
-which must be a slice, map or channel type, or a type parameter,
 optionally followed by a type-specific list of expressions.
+The <a href="#Core_types">core type</a> of <code>T</code> must
+be a slice, map or channel.
 It returns a value of type <code>T</code> (not <code>*T</code>).
 The memory is initialized as described in the section on
 <a href="#The_zero_value">initial values</a>.
 </p>
 
 <pre class="grammar">
-Call             Type T            Result
+Call             Core type    Result
 
 make(T, n)       slice        slice of type T with length n and capacity n
 make(T, n, m)    slice        slice of type T with length n and capacity m
@@ -7698,18 +7628,8 @@ make(T, n)       map               map of type T with initial space for approxim
 
 make(T)          channel      unbuffered channel of type T
 make(T, n)       channel      buffered channel of type T, buffer size n
-
-make(T, n)       type parameter    see below
-make(T, n, m)    type parameter    see below
 </pre>
 
-<p>
-If the first argument is a <a href="#Type_parameter_declarations">type parameter</a>,
-all types in its type set must have the same underlying type, which must be a slice
-or map type, or, if there are channel types, there must only be channel types, they
-must all have the same element type, and the channel directions must not conflict.
-</p>
-
 <p>
 Each of the size arguments <code>n</code> and <code>m</code> must be of <a href="#Numeric_types">integer type</a>,
 have a <a href="#Interface_types">type set</a> containing only integer types,
@@ -7894,7 +7814,7 @@ causes a <a href="#Run_time_panics">run-time panic</a>.
 <p>
 The <code>protect</code> function in the example below invokes
 the function argument <code>g</code> and protects callers from
-run-time panics caused by <code>g</code>.
+run-time panics raised by <code>g</code>.
 </p>
 
 <pre>
@@ -8452,14 +8372,17 @@ func String(ptr *byte, len IntegerType) string
 func StringData(str string) *byte
 </pre>
 
+<!--
+These conversions also apply to type parameters with suitable core types.
+Determine if we can simply use core type instead of underlying type here,
+of if the general conversion rules take care of this.
+-->
+
 <p>
 A <code>Pointer</code> is a <a href="#Pointer_types">pointer type</a> but a <code>Pointer</code>
 value may not be <a href="#Address_operators">dereferenced</a>.
-Any pointer or value of <a href="#Underlying_types">underlying type</a> <code>uintptr</code> can be
-<a href="#Conversions">converted</a> to a type of underlying type <code>Pointer</code> and vice versa.
-If the respective types are <a href="#Type_parameter_declarations">type parameters</a>, all types in
-their respective type sets must have the same underlying type, which must be <code>uintptr</code> and
-<code>Pointer</code>, respectively.
+Any pointer or value of <a href="#Core_types">core type</a> <code>uintptr</code> can be
+<a href="#Conversions">converted</a> to a type of core type <code>Pointer</code> and vice versa.
 The effect of converting between <code>Pointer</code> and <code>uintptr</code> is implementation-defined.
 </p>
 
@@ -8480,7 +8403,7 @@ var p ptr = nil
 <p>
 The functions <code>Alignof</code> and <code>Sizeof</code> take an expression <code>x</code>
 of any type and return the alignment or size, respectively, of a hypothetical variable <code>v</code>
-as if <code>v</code> were declared via <code>var v = x</code>.
+as if <code>v</code> was declared via <code>var v = x</code>.
 </p>
 <p>
 The function <code>Offsetof</code> takes a (possibly parenthesized) <a href="#Selectors">selector</a>
@@ -8764,15 +8687,6 @@ integer values from zero to an upper limit.
 function as range expression.
 </li>
 </ul>
-
-<h4 id="Go_1.24">Go 1.24</h4>
-<ul>
-<li>
-An <a href="#Alias_declarations">alias declaration</a> may declare
-<a href="#Type_parameter_declarations">type parameters</a>.
-</li>
-</ul>
-
 <h3 id="Type_unification_rules">Type unification rules</h3>
 
 <p>
@@ -8813,9 +8727,9 @@ following conditions is true:
 </li>
 <li>
 	Exactly one type is an <a href="#Type_inference">unbound</a>
-	type parameter, and all the types in its type set unify with
-	the other type
-	per the unification rules for <code>≡<sub>A</sub></code>
+	type parameter with a <a href="#Core_types">core type</a>,
+	and that core type unifies with the other type per the
+	unification rules for <code>≡<sub>A</sub></code>
 	(loose unification at the top level and exact unification
 	for element types).
 </li>

doc/godebug.md

@@ -34,7 +34,6 @@ For example, if a Go program is running in an environment that contains
 
 then that Go program will disable the use of HTTP/2 by default in both
 the HTTP client and the HTTP server.
-Unrecognized settings in the `GODEBUG` environment variable are ignored.
 It is also possible to set the default `GODEBUG` for a given program
 (discussed below).
 
@@ -109,9 +108,7 @@ Only the work module's `go.mod` is consulted for `godebug` directives.
 Any directives in required dependency modules are ignored.
 It is an error to list a `godebug` with an unrecognized setting.
 (Toolchains older than Go 1.23 reject all `godebug` lines, since they do not
-understand `godebug` at all.) When a workspace is in use, `godebug`
-directives in `go.mod` files are ignored, and `go.work` will be consulted
-for `godebug` directives instead.
+understand `godebug` at all.)
 
 The defaults from the `go` and `godebug` lines apply to all main
 packages that are built. For more fine-grained control,
@@ -153,100 +150,6 @@ for example,
 see the [runtime documentation](/pkg/runtime#hdr-Environment_Variables)
 and the [go command documentation](/cmd/go#hdr-Build_and_test_caching).
 
-### Go 1.25
-
-Go 1.25 added a new `decoratemappings` setting that controls whether the Go
-runtime annotates OS anonymous memory mappings with context about their
-purpose. These annotations appear in /proc/self/maps and /proc/self/smaps as
-"[anon: Go: ...]". This setting is only used on Linux. For Go 1.25, it defaults
-to `decoratemappings=1`, enabling annotations. Using `decoratemappings=0`
-reverts to the pre-Go 1.25 behavior. This setting is fixed at program startup
-time, and can't be modified by changing the `GODEBUG` environment variable
-after the program starts.
-
-Go 1.25 added a new `embedfollowsymlinks` setting that controls whether the
-Go command will follow symlinks to regular files embedding files.
-The default value `embedfollowsymlinks=0` does not allow following
-symlinks. `embedfollowsymlinks=1` will allow following symlinks.
-
-Go 1.25 corrected the semantics of contention reports for runtime-internal locks,
-and so removed the [`runtimecontentionstacks` setting](/pkg/runtime#hdr-Environment_Variable).
-
-### Go 1.24
-
-Go 1.24 added a new `fips140` setting that controls whether the Go
-Cryptographic Module operates in FIPS 140-3 mode.
-The possible values are:
-- "off": no special support for FIPS 140-3 mode. This is the default.
-- "on": the Go Cryptographic Module operates in FIPS 140-3 mode.
-- "only": like "on", but cryptographic algorithms not approved by
-  FIPS 140-3 return an error or panic.
-For more information, see [FIPS 140-3 Compliance](/doc/security/fips140).
-This setting is fixed at program startup time, and can't be modified
-by changing the `GODEBUG` environment variable after the program starts.
-
-Go 1.24 changed the global [`math/rand.Seed`](/pkg/math/rand/#Seed) to be a
-no-op. This behavior is controlled by the `randseednop` setting.
-For Go 1.24 it defaults to `randseednop=1`.
-Using `randseednop=0` reverts to the pre-Go 1.24 behavior.
-
-Go 1.24 added new values for the `multipathtcp` setting.
-The possible values for `multipathtcp` are now:
-- "0": disable MPTCP on dialers and listeners by default
-- "1": enable MPTCP on dialers and listeners by default
-- "2": enable MPTCP on listeners only by default
-- "3": enable MPTCP on dialers only by default
-
-For Go 1.24, it now defaults to multipathtcp="2", thus
-enabled by default on listeners. Using multipathtcp="0" reverts to the
-pre-Go 1.24 behavior.
-
-Go 1.24 changed the behavior of `go test -json` to emit build errors as JSON
-instead of text.
-These new JSON events are distinguished by new `Action` values,
-but can still cause problems with CI systems that aren't robust to these events.
-This behavior can be controlled with the `gotestjsonbuildtext` setting.
-Using `gotestjsonbuildtext=1` restores the 1.23 behavior.
-This setting will be removed in a future release, Go 1.28 at the earliest.
-
-Go 1.24 changed [`crypto/rsa`](/pkg/crypto/rsa) to require RSA keys to be at
-least 1024 bits. This behavior can be controlled with the `rsa1024min` setting.
-Using `rsa1024min=0` restores the Go 1.23 behavior.
-
-Go 1.24 introduced a mechanism for enabling platform specific Data Independent
-Timing (DIT) modes in the [`crypto/subtle`](/pkg/crypto/subtle) package. This
-mode can be enabled for an entire program with the `dataindependenttiming` setting.
-For Go 1.24 it defaults to `dataindependenttiming=0`. There is no change in default
-behavior from Go 1.23 when `dataindependenttiming` is unset.
-Using `dataindependenttiming=1` enables the DIT mode for the entire Go program.
-When enabled, DIT will be enabled when calling into C from Go. When enabled,
-calling into Go code from C will enable DIT, and disable it before returning to
-C if it was not enabled when Go code was entered.
-This currently only affects arm64 programs. For all other platforms it is a no-op.
-
-Go 1.24 removed the `x509sha1` setting.  `crypto/x509` no longer supports verifying
-signatures on certificates that use SHA-1 based signature algorithms.
-
-Go 1.24 changes the default value of the [`x509usepolicies`
-setting.](/pkg/crypto/x509/#CreateCertificate) from `0` to `1`. When marshalling
-certificates, policies are now taken from the
-[`Certificate.Policies`](/pkg/crypto/x509/#Certificate.Policies) field rather
-than the
-[`Certificate.PolicyIdentifiers`](/pkg/crypto/x509/#Certificate.PolicyIdentifiers)
-field by default.
-
-Go 1.24 enabled the post-quantum key exchange mechanism
-X25519MLKEM768 by default. The default can be reverted using the
-[`tlsmlkem` setting](/pkg/crypto/tls/#Config.CurvePreferences).
-This can be useful when dealing with buggy TLS servers that do not handle large records correctly,
-causing a timeout during the handshake (see [TLS post-quantum TL;DR fail](https://tldr.fail/)).
-Go 1.24 also removed X25519Kyber768Draft00 and the Go 1.23 `tlskyber` setting.
-
-Go 1.24 made [`ParsePKCS1PrivateKey`](/pkg/crypto/x509/#ParsePKCS1PrivateKey)
-use and validate the CRT parameters in the encoded private key. This behavior
-can be controlled with the `x509rsacrt` setting. Using `x509rsacrt=0` restores
-the Go 1.23 behavior.
-
 ### Go 1.23
 
 Go 1.23 changed the channels created by package time to be unbuffered
@@ -276,8 +179,6 @@ Previous versions default to `winreadlinkvolume=0`.
 Go 1.23 enabled the experimental post-quantum key exchange mechanism
 X25519Kyber768Draft00 by default. The default can be reverted using the
 [`tlskyber` setting](/pkg/crypto/tls/#Config.CurvePreferences).
-This can be useful when dealing with buggy TLS servers that do not handle large records correctly,
-causing a timeout during the handshake (see [TLS post-quantum TL;DR fail](https://tldr.fail/)).
 
 Go 1.23 changed the behavior of
 [crypto/x509.ParseCertificate](/pkg/crypto/x509/#ParseCertificate) to reject
@@ -373,7 +274,7 @@ certificate policy OIDs with components larger than 31 bits. By default this
 field is only used during parsing, when it is populated with policy OIDs, but
 not used during marshaling. It can be used to marshal these larger OIDs, instead
 of the existing PolicyIdentifiers field, by using the
-[`x509usepolicies` setting](/pkg/crypto/x509/#CreateCertificate).
+[`x509usepolicies` setting.](/pkg/crypto/x509/#CreateCertificate).
 
 
 ### Go 1.21
@@ -441,7 +342,7 @@ There is no plan to remove this setting.
 
 Go 1.18 removed support for SHA1 in most X.509 certificates,
 controlled by the [`x509sha1` setting](/pkg/crypto/x509#InsecureAlgorithmError).
-This setting was removed in Go 1.24.
+This setting will be removed in a future release, Go 1.22 at the earliest.
 
 ### Go 1.10
 

doc/initial/1-intro.md

@@ -1,3 +1,9 @@
+<!--
+NOTE: In this document and others in this directory, the convention is to
+set fixed-width phrases with non-fixed-width spaces, as in
+`hello` `world`.
+-->
+
 <style>
   main ul li { margin: 0.5em 0; }
 </style>

doc/initial/6-stdlib/99-minor/0-heading.md

@@ -1,10 +1,3 @@
 ### Minor changes to the library {#minor_library_changes}
 
-#### go/types
 
-The `Var.Kind` method returns an enumeration of type `VarKind` that
-classifies the variable (package-level, local, receiver, parameter,
-result, or struct field). See issue #70250.
-
-Callers of `NewVar` or `NewParam` are encouraged to call `Var.SetKind`
-to ensure that this attribute is set correctly in all cases.

doc/next/1-intro.md

@@ -1,8 +0,0 @@
-<style>
-  main ul li { margin: 0.5em 0; }
-</style>
-
-## DRAFT RELEASE NOTES — Introduction to Go 1.N {#introduction}
-
-**Go 1.25 is not yet released. These are work-in-progress release notes.
-Go 1.25 is expected to be released in August 2025.**

doc/next/2-language.md

@@ -1,3 +0,0 @@
-## Changes to the language {#language}
-
-

doc/next/3-tools.md

@@ -1,42 +0,0 @@
-## Tools {#tools}
-
-### Go command {#go-command}
-
-The `go build` `-asan` option now defaults to doing leak detection at
-program exit.
-This will report an error if memory allocated by C is not freed and is
-not referenced by any other memory allocated by either C or Go.
-These new error reports may be disabled by setting
-`ASAN_OPTIONS=detect_leaks=0` in the environment when running the
-program.
-
-<!-- go.dev/issue/71294 -->
-
-The new `work` package pattern matches all packages in the work (formerly called main)
-modules: either the single work module in module mode or the set of workspace modules
-in workspace mode.
-
-<!-- go.dev/issue/65847 -->
-
-When the go command updates the `go` line in a `go.mod` or `go.work` file,
-it [no longer](/ref/mod#go-mod-file-toolchain) adds a toolchain line
-specifying the command's current version.
-
-### Cgo {#cgo}
-
-### Vet {#vet}
-
-The `go vet` command includes new analyzers:
-
-<!-- go.dev/issue/18022 -->
-
-- [waitgroup](https://pkg.go.dev/golang.org/x/tools/go/analysis/passes/waitgroup),
-  which reports misplaced calls to [sync.WaitGroup.Add]; and
-
-<!-- go.dev/issue/28308 -->
-
-- [hostport](https://pkg.go.dev/golang.org/x/tools/go/analysis/passes/hostport),
-  which reports uses of `fmt.Sprintf("%s:%d", host, port)` to
-  construct addresses for [net.Dial], as these will not work with
-  IPv6; instead it suggests using [net.JoinHostPort].
-

doc/next/4-runtime.md

@@ -1,26 +0,0 @@
-## Runtime {#runtime}
-
-<!-- go.dev/issue/71517 -->
-
-The message printed when a program exits due to an unhandled panic
-that was recovered and repanicked no longer repeats the text of
-the panic value.
-
-Previously, a program which panicked with `panic("PANIC")`,
-recovered the panic, and then repanicked with the original
-value would print:
-
-    panic: PANIC [recovered]
-      panic: PANIC
-
-This program will now print:
-
-    panic: PANIC [recovered, repanicked]
-
-<!-- go.dev/issue/71546 -->
-
-On Linux systems with kernel support for anonymous VMA names
-(`CONFIG_ANON_VMA_NAME`), the Go runtime will annotate anonymous memory
-mappings with context about their purpose. e.g., `[anon: Go: heap]` for heap
-memory. This can be disabled with the [GODEBUG setting](/doc/godebug)
-`decoratemappings=0`.

doc/next/5-toolchain.md

@@ -1,44 +0,0 @@
-## Compiler {#compiler}
-
-<!-- https://go.dev/issue/26379 -->
-
-The compiler and linker in Go 1.25 now generate debug information
-using [DWARF version 5](https://dwarfstd.org/dwarf5std.html); the
-newer DWARF version reduces the space required for debugging
-information in Go binaries.
-DWARF 5 generation is gated by the "dwarf5" GOEXPERIMENT; this
-functionality can be disabled (for now) using GOEXPERIMENT=nodwarf5.
-
-<!-- https://go.dev/issue/72860, CL 657715 -->
-
-The compiler [has been fixed](/cl/657715)
-to ensure that nil pointer checks are performed promptly. Programs like the following,
-which used to execute successfully, will now panic with a nil-pointer exception:
-
-```
-package main
-
-import "os"
-
-func main() {
-	f, err := os.Open("nonExistentFile")
-	name := f.Name()
-	if err != nil {
-		return
-	}
-	println(name)
-}
-```
-
-This program is incorrect in that it uses the result of `os.Open` before checking
-the error. The main result of `os.Open` can be a nil pointer if the error result is non-nil.
-But because of [a compiler bug](/issue/72860), this program ran successfully under
-Go versions 1.21 through 1.24 (in violation of the Go spec). It will no longer run
-successfully in Go 1.25. If this change is affecting your code, the solution is to put
-the non-nil error check earlier in your code, preferably immediately after
-the error-generating statement.
-
-## Assembler {#assembler}
-
-## Linker {#linker}
-

doc/next/6-stdlib/0-heading.md

@@ -1,2 +0,0 @@
-## Standard library {#library}
-

doc/next/6-stdlib/99-minor/0-heading.md

@@ -1,3 +0,0 @@
-### Minor changes to the library {#minor_library_changes}
-
-

doc/next/6-stdlib/99-minor/README

@@ -1 +0,0 @@
-API changes and other small changes to the standard library go here.

doc/next/6-stdlib/99-minor/archive/tar/49580.md

@@ -1,2 +0,0 @@
-The [*Writer.AddFS] implementation now supports symbolic links
-for filesystems that implement [io/fs.ReadLinkFS].

doc/next/6-stdlib/99-minor/crypto/elliptic/hidden.md

@@ -1,2 +0,0 @@
-The hidden and undocumented `Inverse` and `CombinedMult` methods on some [Curve]
-implementations have been removed.

doc/next/6-stdlib/99-minor/crypto/tls/67516.md

@@ -1,2 +0,0 @@
-The new [ConnectionState.CurveID] field exposes the key exchange mechanism used
-to establish the connection.

doc/next/6-stdlib/99-minor/crypto/tls/fips.md

@@ -1,2 +0,0 @@
-When [FIPS 140-3 mode](/doc/security/fips140) is enabled, Extended Master Secret
-is now required in TLS 1.2, and Ed25519 and X25519MLKEM768 are now allowed.

doc/next/6-stdlib/99-minor/debug/elf/72843.md

@@ -1,4 +0,0 @@
-The [debug/elf] package adds two new constants:
-- [PT_RISCV_ATTRIBUTES]
-- [SHT_RISCV_ATTRIBUTES]
-for RISC-V ELF parsing.

doc/next/6-stdlib/99-minor/go/parser/71122.md

@@ -1 +0,0 @@
-The [ParseDir] function is deprecated.

doc/next/6-stdlib/99-minor/go/types/70250.md

@@ -1,3 +0,0 @@
-[Var] now has a [Var.Kind] method that classifies the variable as one
-of: package-level, receiver, parameter, result, or local variable, or
-a struct field.

doc/next/6-stdlib/99-minor/go/types/70737.md

@@ -1,3 +0,0 @@
-The new [LookupSelection] function looks up the field or method of a
-given name and receiver type, like the existing [LookupFieldOrMethod]
-function, but returns the result in the form of a [Selection].

doc/next/6-stdlib/99-minor/io/fs/49580.md

@@ -1 +0,0 @@
-A new [ReadLinkFS] interface provides the ability to read symbolic links in a filesystem.

doc/next/6-stdlib/99-minor/log/slog/70280.md

@@ -1 +0,0 @@
-[Record] now has a Source() method, returning its source location or nil if unavailable.

doc/next/6-stdlib/99-minor/mime/multipart/46771.md

@@ -1,2 +0,0 @@
-The new helper function [FieldContentDisposition] builds multipart
-Content-Disposition header fields.

doc/next/6-stdlib/99-minor/net/10350.md

@@ -1,3 +0,0 @@
-On Windows, the [TCPConn.File], [UDPConn.File], [UnixConn.File],
-[IPConn.File], [TCPListener.File], and [UnixListener.File]
-methods are now supported.

doc/next/6-stdlib/99-minor/net/56025.md

@@ -1,5 +0,0 @@
-[LookupMX] and [*Resolver.LookupMX] now return DNS names that look
-like valid IP address, as well as valid domain names.
-Previously if a name server returned an IP address as a DNS name,
-LookupMX would discard it, as required by the RFCs.
-However, name servers in practice do sometimes return IP addresses.

doc/next/6-stdlib/99-minor/net/63529.md

@@ -1 +0,0 @@
-On Windows, the [ListenMulticastUDP] now supports IPv6 addresses.

doc/next/6-stdlib/99-minor/net/9503.md

@@ -1,2 +0,0 @@
-On Windows, the [FileConn], [FilePacketConn], [FileListener]
-functions are now supported.

doc/next/6-stdlib/99-minor/os/15388.md

@@ -1,14 +0,0 @@
-On Windows, [NewFile] now supports handles opened for asynchronous I/O (that is,
-[syscall.FILE_FLAG_OVERLAPPED] is specified in the [syscall.CreateFile] call).
-These handles are associated with the Go runtime's I/O completion port,
-which provides the following benefits for the resulting [File]:
-
-- I/O methods ([File.Read], [File.Write], [File.ReadAt], and [File.WriteAt]) do not block an OS thread.
-- Deadline methods ([File.SetDeadline], [File.SetReadDeadline], and [File.SetWriteDeadline]) are supported.
-
-This enhancement is especially beneficial for applications that communicate via named pipes on Windows.
-
-Note that a handle can only be associated with one completion port at a time.
-If the handle provided to [NewFile] is already associated with a completion port,
-the returned [File] is downgraded to synchronous I/O mode.
-In this case, I/O methods will block an OS thread, and the deadline methods have no effect.

doc/next/6-stdlib/99-minor/os/49580.md

@@ -1,2 +0,0 @@
-The filesystem returned by [DirFS] implements the new [io/fs.ReadLinkFS] interface.
-[CopyFS] supports symlinks when copying filesystems that implement [io/fs.ReadLinkFS].

doc/next/6-stdlib/99-minor/os/67002.md

@@ -1,10 +0,0 @@
-The [os.Root] type supports the following additional methods:
-
-  * [os.Root.Chmod]
-  * [os.Root.Chown]
-  * [os.Root.Chtimes]
-  * [os.Root.Lchown]
-  * [os.Root.Link]
-  * [os.Root.Readlink]
-  * [os.Root.Rename]
-  * [os.Root.Symlink]

doc/next/6-stdlib/99-minor/regexp/syntax/70781.md

@@ -1,4 +0,0 @@
-The `\p{name}` and `\P{name}` character class syntaxes now accept the names
-Any, ASCII, Assigned, Cn, and LC, as well as Unicode category aliases like `\p{Letter}` for `\pL`.
-Following [Unicode TR18](https://unicode.org/reports/tr18/), they also now use
-case-insensitive name lookups, ignoring spaces, underscores, and hyphens.

doc/next/6-stdlib/99-minor/runtime/pprof/66999.md

@@ -1,6 +0,0 @@
-The mutex profile for contention on runtime-internal locks now correctly points
-to the end of the critical section that caused the delay. This matches the
-profile's behavior for contention on `sync.Mutex` values. The
-`runtimecontentionstacks` setting for `GODEBUG`, which allowed opting in to the
-unusual behavior of Go 1.22 through 1.24 for this part of the profile, is now
-gone.

doc/next/6-stdlib/99-minor/sync/63769.md

@@ -1,2 +0,0 @@
-[WaitGroup] has added a new method [WaitGroup.Go],
-that makes the common pattern of creating and counting goroutines more convenient.

doc/next/6-stdlib/99-minor/testing/fstest/49580.md

@@ -1,3 +0,0 @@
-[MapFS] implements the new [io/fs.ReadLinkFS] interface.
-[TestFS] will verify the functionality of the [io/fs.ReadLinkFS] interface if implemented.
-[TestFS] will no longer follow symlinks to avoid unbounded recursion.

doc/next/6-stdlib/99-minor/unicode/70780.md

@@ -1,4 +0,0 @@
-The new [CategoryAliases] map provides access to category alias names, such as “Letter” for “L”.
-The new categories [Cn] and [LC] define unassigned codepoints and cased letters, respectively.
-These have always been defined by Unicode but were inadvertently omitted in earlier versions of Go.
-The [C] category now includes [Cn], meaning it has added all unassigned code points.

doc/next/7-ports.md

@@ -1,11 +0,0 @@
-## Ports {#ports}
-
-### Darwin
-
-<!-- go.dev/issue/69839 -->
-As [announced](/doc/go1.24#darwin) in the Go 1.24 release notes, Go 1.25 requires macOS 12 Monterey or later; support for previous versions has been discontinued.
-
-### Windows
-
-<!-- go.dev/issue/71671 -->
-Go 1.25 is the last release that contains the [broken](/doc/go1.24#windows) 32-bit windows/arm port (`GOOS=windows` `GOARCH=arm`). It will be removed in Go 1.26.

lib/fips140/Makefile

@@ -1,46 +0,0 @@
-# Copyright 2024 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.
-
-# Rules for building and testing new FIPS snapshots.
-# For example:
-#
-#	make v1.2.3.zip
-#	make v1.2.3.test
-#
-# and then if changes are needed, check them into master
-# and run 'make v1.2.3.rm' and repeat.
-#
-# Note that once published a snapshot zip file should never
-# be modified. We record the sha256 hashes of the zip files
-# in fips140.sum, and the cmd/go/internal/fips140 test checks
-# that the zips match.
-#
-# When the zip file is finalized, run 'make updatesum' to update
-# fips140.sum.
-
-default:
-	@echo nothing to make
-
-# make v1.2.3.zip builds a v1.2.3.zip file
-# from the current origin/master.
-# copy and edit the 'go run' command by hand to use a different branch.
-v%.zip:
-	git fetch origin master
-	go run ../../src/cmd/go/internal/fips140/mkzip.go v$*
-
-# normally mkzip refuses to overwrite an existing zip file.
-# make v1.2.3.rm removes the zip file and and unpacked
-# copy from the module cache.
-v%.rm:
-	rm -f v$*.zip
-	chmod -R u+w $$(go env GOMODCACHE)/golang.org/fips140@v$* 2>/dev/null || true
-	rm -rf $$(go env GOMODCACHE)/golang.org/fips140@v$*
-
-# make v1.2.3.test runs the crypto tests using that snapshot.
-v%.test:
-	GOFIPS140=v$* go test -short crypto...
-
-# make updatesum updates the fips140.sum file.
-updatesum:
-	go test cmd/go/internal/fips140 -update

lib/fips140/README.md

@@ -1,9 +0,0 @@
-This directory holds snapshots of the crypto/internal/fips140 tree
-that are being validated and certified for FIPS-140 use.
-The file x.txt (for example, inprocess.txt, certified.txt)
-defines the meaning of the FIPS version alias x, listing
-the exact version to use.
-
-The zip files are created by cmd/go/internal/fips140/mkzip.go.
-The fips140.sum file lists checksums for the zip files.
-See the Makefile for recipes.

lib/fips140/fips140.sum

@@ -1,12 +0,0 @@
-# SHA256 checksums of snapshot zip files in this directory.
-# These checksums are included in the FIPS security policy
-# (validation instructions sent to the lab) and MUST NOT CHANGE.
-# That is, the zip files themselves must not change.
-#
-# It is okay to add new zip files to the list, and it is okay to
-# remove zip files from the list when they are removed from
-# this directory. To update this file:
-#
-#	go test cmd/go/internal/fips140 -update
-#
-v1.0.0.zip b50508feaeff05d22516b21e1fd210bbf5d6a1e422eaf2cfa23fe379342713b8

lib/time/update.bash

@@ -24,8 +24,8 @@
 # in the CL match the update.bash in the CL.
 
 # Versions to use.
-CODE=2025a
-DATA=2025a
+CODE=2024a
+DATA=2024a
 
 set -e
 
@@ -40,12 +40,7 @@ curl -sS -L -O https://www.iana.org/time-zones/repository/releases/tzdata$DATA.t
 tar xzf tzcode$CODE.tar.gz
 tar xzf tzdata$DATA.tar.gz
 
-# The PACKRATLIST and PACKRATDATA options are copied from Ubuntu:
-# https://git.launchpad.net/ubuntu/+source/tzdata/tree/debian/rules?h=debian/sid
-#
-# You can see the description of these make variables in the tzdata Makefile:
-# https://github.com/eggert/tz/blob/main/Makefile
-if ! make CFLAGS=-DSTD_INSPIRED AWK=awk TZDIR=zoneinfo PACKRATDATA=backzone PACKRATLIST=zone.tab posix_only >make.out 2>&1; then
+if ! make CFLAGS=-DSTD_INSPIRED AWK=awk TZDIR=zoneinfo posix_only >make.out 2>&1; then
 	cat make.out
 	exit 2
 fi

misc/linkcheck/linkcheck.go

@@ -0,0 +1,191 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// The linkcheck command finds missing links in the godoc website.
+// It crawls a URL recursively and notes URLs and URL fragments
+// that it's seen and prints a report of missing links at the end.
+package main
+
+import (
+	"errors"
+	"flag"
+	"fmt"
+	"io"
+	"log"
+	"net/http"
+	"os"
+	"regexp"
+	"strings"
+	"sync"
+)
+
+var (
+	root    = flag.String("root", "http://localhost:6060", "Root to crawl")
+	verbose = flag.Bool("verbose", false, "verbose")
+)
+
+var wg sync.WaitGroup        // outstanding fetches
+var urlq = make(chan string) // URLs to crawl
+
+// urlFrag is a URL and its optional #fragment (without the #)
+type urlFrag struct {
+	url, frag string
+}
+
+var (
+	mu          sync.Mutex
+	crawled     = make(map[string]bool)      // URL without fragment -> true
+	neededFrags = make(map[urlFrag][]string) // URL#frag -> who needs it
+)
+
+var aRx = regexp.MustCompile(`<a href=['"]?(/[^\s'">]+)`)
+
+// Owned by crawlLoop goroutine:
+var (
+	linkSources = make(map[string][]string) // url no fragment -> sources
+	fragExists  = make(map[urlFrag]bool)
+	problems    []string
+)
+
+func localLinks(body string) (links []string) {
+	seen := map[string]bool{}
+	mv := aRx.FindAllStringSubmatch(body, -1)
+	for _, m := range mv {
+		ref := m[1]
+		if strings.HasPrefix(ref, "/src/") {
+			continue
+		}
+		if !seen[ref] {
+			seen[ref] = true
+			links = append(links, m[1])
+		}
+	}
+	return
+}
+
+var idRx = regexp.MustCompile(`\bid=['"]?([^\s'">]+)`)
+
+func pageIDs(body string) (ids []string) {
+	mv := idRx.FindAllStringSubmatch(body, -1)
+	for _, m := range mv {
+		ids = append(ids, m[1])
+	}
+	return
+}
+
+// url may contain a #fragment, and the fragment is then noted as needing to exist.
+func crawl(url string, sourceURL string) {
+	if strings.Contains(url, "/devel/release") {
+		return
+	}
+	mu.Lock()
+	defer mu.Unlock()
+	if u, frag, ok := strings.Cut(url, "#"); ok {
+		url = u
+		if frag != "" {
+			uf := urlFrag{url, frag}
+			neededFrags[uf] = append(neededFrags[uf], sourceURL)
+		}
+	}
+	if crawled[url] {
+		return
+	}
+	crawled[url] = true
+
+	wg.Add(1)
+	go func() {
+		urlq <- url
+	}()
+}
+
+func addProblem(url, errmsg string) {
+	msg := fmt.Sprintf("Error on %s: %s (from %s)", url, errmsg, linkSources[url])
+	if *verbose {
+		log.Print(msg)
+	}
+	problems = append(problems, msg)
+}
+
+func crawlLoop() {
+	for url := range urlq {
+		if err := doCrawl(url); err != nil {
+			addProblem(url, err.Error())
+		}
+	}
+}
+
+func doCrawl(url string) error {
+	defer wg.Done()
+
+	req, err := http.NewRequest("GET", url, nil)
+	if err != nil {
+		return err
+	}
+	res, err := http.DefaultTransport.RoundTrip(req)
+	if err != nil {
+		return err
+	}
+	// Handle redirects.
+	if res.StatusCode/100 == 3 {
+		newURL, err := res.Location()
+		if err != nil {
+			return fmt.Errorf("resolving redirect: %v", err)
+		}
+		if !strings.HasPrefix(newURL.String(), *root) {
+			// Skip off-site redirects.
+			return nil
+		}
+		crawl(newURL.String(), url)
+		return nil
+	}
+	if res.StatusCode != 200 {
+		return errors.New(res.Status)
+	}
+	slurp, err := io.ReadAll(res.Body)
+	res.Body.Close()
+	if err != nil {
+		log.Fatalf("Error reading %s body: %v", url, err)
+	}
+	if *verbose {
+		log.Printf("Len of %s: %d", url, len(slurp))
+	}
+	body := string(slurp)
+	for _, ref := range localLinks(body) {
+		if *verbose {
+			log.Printf("  links to %s", ref)
+		}
+		dest := *root + ref
+		linkSources[dest] = append(linkSources[dest], url)
+		crawl(dest, url)
+	}
+	for _, id := range pageIDs(body) {
+		if *verbose {
+			log.Printf(" url %s has #%s", url, id)
+		}
+		fragExists[urlFrag{url, id}] = true
+	}
+	return nil
+}
+
+func main() {
+	flag.Parse()
+
+	go crawlLoop()
+	crawl(*root, "")
+
+	wg.Wait()
+	close(urlq)
+	for uf, needers := range neededFrags {
+		if !fragExists[uf] {
+			problems = append(problems, fmt.Sprintf("Missing fragment for %+v from %v", uf, needers))
+		}
+	}
+
+	for _, s := range problems {
+		fmt.Println(s)
+	}
+	if len(problems) > 0 {
+		os.Exit(1)
+	}
+}

misc/wasm/wasm_exec.html

@@ -17,7 +17,7 @@ license that can be found in the LICENSE file.
 	<script src="https://cdn.jsdelivr.net/npm/text-encoding@0.7.0/lib/encoding.min.js"></script>
 	(see https://caniuse.com/#feat=textencoder)
 	-->
-	<script src="../../lib/wasm/wasm_exec.js"></script>
+	<script src="wasm_exec.js"></script>
 	<script>
 		if (!WebAssembly.instantiateStreaming) { // polyfill
 			WebAssembly.instantiateStreaming = async (resp, importObject) => {

misc/wasm/wasm_exec.js

@@ -14,7 +14,7 @@
 	if (!globalThis.fs) {
 		let outputBuf = "";
 		globalThis.fs = {
-			constants: { O_WRONLY: -1, O_RDWR: -1, O_CREAT: -1, O_TRUNC: -1, O_APPEND: -1, O_EXCL: -1, O_DIRECTORY: -1 }, // unused
+			constants: { O_WRONLY: -1, O_RDWR: -1, O_CREAT: -1, O_TRUNC: -1, O_APPEND: -1, O_EXCL: -1 }, // unused
 			writeSync(fd, buf) {
 				outputBuf += decoder.decode(buf);
 				const nl = outputBuf.lastIndexOf("\n");
@@ -73,14 +73,6 @@
 		}
 	}
 
-	if (!globalThis.path) {
-		globalThis.path = {
-			resolve(...pathSegments) {
-				return pathSegments.join("/");
-			}
-		}
-	}
-
 	if (!globalThis.crypto) {
 		throw new Error("globalThis.crypto is not available, polyfill required (crypto.getRandomValues only)");
 	}
@@ -216,16 +208,10 @@
 				return decoder.decode(new DataView(this._inst.exports.mem.buffer, saddr, len));
 			}
 
-			const testCallExport = (a, b) => {
-				this._inst.exports.testExport0();
-				return this._inst.exports.testExport(a, b);
-			}
-
 			const timeOrigin = Date.now() - performance.now();
 			this.importObject = {
 				_gotest: {
 					add: (a, b) => a + b,
-					callExport: testCallExport,
 				},
 				gojs: {
 					// Go's SP does not change as long as no Go code is running. Some operations (e.g. calls, getters and setters)

misc/wasm/wasm_exec_node.js

@@ -11,7 +11,6 @@ if (process.argv.length < 3) {
 
 globalThis.require = require;
 globalThis.fs = require("fs");
-globalThis.path = require("path");
 globalThis.TextEncoder = require("util").TextEncoder;
 globalThis.TextDecoder = require("util").TextDecoder;
 

src/README.vendor

@@ -33,10 +33,6 @@ Before updating vendor directories, ensure that module mode is enabled.
 Make sure that GO111MODULE is not set in the environment, or that it is
 set to 'on' or 'auto', and if you use a go.work file, set GOWORK=off.
 
-Also, ensure that 'go env GOROOT' shows the root of this Go source
-tree. Otherwise, the results are undefined. It's recommended to build
-Go from source and use that 'go' binary to update its source tree.
-
 Requirements may be added, updated, and removed with 'go get'.
 The vendor directory may be updated with 'go mod vendor'.
 A typical sequence might be:

src/all.bat

@@ -6,11 +6,17 @@
 
 setlocal
 
-if not exist make.bat (
+if exist make.bat goto ok
 echo all.bat must be run from go\src
-    exit /b 1
-)
+:: cannot exit: would kill parent command interpreter
+goto end
+:ok
 
-call .\make.bat --no-banner || exit /b 1
-call .\run.bat --no-rebuild || exit /b 1
-..\bin\go tool dist banner
+call .\make.bat --no-banner --no-local
+if %GOBUILDFAIL%==1 goto end
+call .\run.bat --no-rebuild --no-local
+if %GOBUILDFAIL%==1 goto end
+"%GOTOOLDIR%/dist" banner
+
+:end
+if x%GOBUILDEXIT%==x1 exit %GOBUILDFAIL%

src/archive/tar/common.go

@@ -15,7 +15,6 @@ import (
 	"fmt"
 	"internal/godebug"
 	"io/fs"
-	"maps"
 	"math"
 	"path"
 	"reflect"
@@ -697,14 +696,24 @@ func FileInfoHeader(fi fs.FileInfo, link string) (*Header, error) {
 		h.Gname = sys.Gname
 		h.AccessTime = sys.AccessTime
 		h.ChangeTime = sys.ChangeTime
-		h.Xattrs = maps.Clone(sys.Xattrs)
+		if sys.Xattrs != nil {
+			h.Xattrs = make(map[string]string)
+			for k, v := range sys.Xattrs {
+				h.Xattrs[k] = v
+			}
+		}
 		if sys.Typeflag == TypeLink {
 			// hard link
 			h.Typeflag = TypeLink
 			h.Size = 0
 			h.Linkname = sys.Linkname
 		}
-		h.PAXRecords = maps.Clone(sys.PAXRecords)
+		if sys.PAXRecords != nil {
+			h.PAXRecords = make(map[string]string)
+			for k, v := range sys.PAXRecords {
+				h.PAXRecords[k] = v
+			}
+		}
 	}
 	var doNameLookups = true
 	if iface, ok := fi.(FileInfoNames); ok {

src/archive/tar/reader_test.go

@@ -7,16 +7,14 @@ package tar
 import (
 	"bytes"
 	"compress/bzip2"
+	"crypto/md5"
 	"errors"
 	"fmt"
-	"hash/crc32"
 	"io"
-	"maps"
 	"math"
 	"os"
 	"path"
 	"reflect"
-	"slices"
 	"strconv"
 	"strings"
 	"testing"
@@ -27,7 +25,7 @@ func TestReader(t *testing.T) {
 	vectors := []struct {
 		file    string    // Test input file
 		headers []*Header // Expected output headers
-		chksums []string  // CRC32 checksum of files, leave as nil if not checked
+		chksums []string  // MD5 checksum of files, leave as nil if not checked
 		err     error     // Expected error to occur
 	}{{
 		file: "testdata/gnu.tar",
@@ -55,8 +53,8 @@ func TestReader(t *testing.T) {
 			Format:   FormatGNU,
 		}},
 		chksums: []string{
-			"6cbd88fc",
-			"ddac04b3",
+			"e38b27eaccb4391bdec553a7f3ae6b2f",
+			"c65bd2e50a56a2138bf1716f2fd56fe9",
 		},
 	}, {
 		file: "testdata/sparse-formats.tar",
@@ -149,11 +147,11 @@ func TestReader(t *testing.T) {
 			Format:   FormatGNU,
 		}},
 		chksums: []string{
-			"5375e1d2",
-			"5375e1d2",
-			"5375e1d2",
-			"5375e1d2",
-			"8eb179ba",
+			"6f53234398c2449fe67c1812d993012f",
+			"6f53234398c2449fe67c1812d993012f",
+			"6f53234398c2449fe67c1812d993012f",
+			"6f53234398c2449fe67c1812d993012f",
+			"b0061974914468de549a2af8ced10316",
 		},
 	}, {
 		file: "testdata/star.tar",
@@ -270,7 +268,7 @@ func TestReader(t *testing.T) {
 			Format: FormatPAX,
 		}},
 		chksums: []string{
-			"5fd7e86a",
+			"0afb597b283fe61b5d4879669a350556",
 		},
 	}, {
 		file: "testdata/pax-records.tar",
@@ -657,7 +655,7 @@ func TestReader(t *testing.T) {
 				if v.chksums == nil {
 					continue
 				}
-				h := crc32.NewIEEE()
+				h := md5.New()
 				_, err = io.CopyBuffer(h, tr, rdbuf) // Effectively an incremental read
 				if err != nil {
 					break
@@ -1019,7 +1017,7 @@ func TestParsePAX(t *testing.T) {
 	for i, v := range vectors {
 		r := strings.NewReader(v.in)
 		got, err := parsePAX(r)
-		if !maps.Equal(got, v.want) && !(len(got) == 0 && len(v.want) == 0) {
+		if !reflect.DeepEqual(got, v.want) && !(len(got) == 0 && len(v.want) == 0) {
 			t.Errorf("test %d, parsePAX():\ngot  %v\nwant %v", i, got, v.want)
 		}
 		if ok := err == nil; ok != v.ok {
@@ -1136,7 +1134,7 @@ func TestReadOldGNUSparseMap(t *testing.T) {
 		v.input = v.input[copy(blk[:], v.input):]
 		tr := Reader{r: bytes.NewReader(v.input)}
 		got, err := tr.readOldGNUSparseMap(&hdr, &blk)
-		if !slices.Equal(got, v.wantMap) {
+		if !equalSparseEntries(got, v.wantMap) {
 			t.Errorf("test %d, readOldGNUSparseMap(): got %v, want %v", i, got, v.wantMap)
 		}
 		if err != v.wantErr {
@@ -1327,7 +1325,7 @@ func TestReadGNUSparsePAXHeaders(t *testing.T) {
 		r := strings.NewReader(v.inputData + "#") // Add canary byte
 		tr := Reader{curr: &regFileReader{r, int64(r.Len())}}
 		got, err := tr.readGNUSparsePAXHeaders(&hdr)
-		if !slices.Equal(got, v.wantMap) {
+		if !equalSparseEntries(got, v.wantMap) {
 			t.Errorf("test %d, readGNUSparsePAXHeaders(): got %v, want %v", i, got, v.wantMap)
 		}
 		if err != v.wantErr {

src/archive/tar/tar_test.go

@@ -11,13 +11,11 @@ import (
 	"internal/testenv"
 	"io"
 	"io/fs"
-	"maps"
 	"math"
 	"os"
 	"path"
 	"path/filepath"
 	"reflect"
-	"slices"
 	"strings"
 	"testing"
 	"time"
@@ -100,6 +98,10 @@ func (f *testFile) Seek(pos int64, whence int) (int64, error) {
 	return f.pos, nil
 }
 
+func equalSparseEntries(x, y []sparseEntry) bool {
+	return (len(x) == 0 && len(y) == 0) || reflect.DeepEqual(x, y)
+}
+
 func TestSparseEntries(t *testing.T) {
 	vectors := []struct {
 		in   []sparseEntry
@@ -196,11 +198,11 @@ func TestSparseEntries(t *testing.T) {
 			continue
 		}
 		gotAligned := alignSparseEntries(append([]sparseEntry{}, v.in...), v.size)
-		if !slices.Equal(gotAligned, v.wantAligned) {
+		if !equalSparseEntries(gotAligned, v.wantAligned) {
 			t.Errorf("test %d, alignSparseEntries():\ngot  %v\nwant %v", i, gotAligned, v.wantAligned)
 		}
 		gotInverted := invertSparseEntries(append([]sparseEntry{}, v.in...), v.size)
-		if !slices.Equal(gotInverted, v.wantInverted) {
+		if !equalSparseEntries(gotInverted, v.wantInverted) {
 			t.Errorf("test %d, inverseSparseEntries():\ngot  %v\nwant %v", i, gotInverted, v.wantInverted)
 		}
 	}
@@ -742,7 +744,7 @@ func TestHeaderAllowedFormats(t *testing.T) {
 		if formats != v.formats {
 			t.Errorf("test %d, allowedFormats(): got %v, want %v", i, formats, v.formats)
 		}
-		if formats&FormatPAX > 0 && !maps.Equal(paxHdrs, v.paxHdrs) && !(len(paxHdrs) == 0 && len(v.paxHdrs) == 0) {
+		if formats&FormatPAX > 0 && !reflect.DeepEqual(paxHdrs, v.paxHdrs) && !(len(paxHdrs) == 0 && len(v.paxHdrs) == 0) {
 			t.Errorf("test %d, allowedFormats():\ngot  %v\nwant %s", i, paxHdrs, v.paxHdrs)
 		}
 		if (formats != FormatUnknown) && (err != nil) {

src/archive/tar/writer.go

@@ -9,7 +9,6 @@ import (
 	"fmt"
 	"io"
 	"io/fs"
-	"maps"
 	"path"
 	"slices"
 	"strings"
@@ -170,10 +169,16 @@ func (tw *Writer) writePAXHeader(hdr *Header, paxHdrs map[string]string) error {
 	// Write PAX records to the output.
 	isGlobal := hdr.Typeflag == TypeXGlobalHeader
 	if len(paxHdrs) > 0 || isGlobal {
+		// Sort keys for deterministic ordering.
+		var keys []string
+		for k := range paxHdrs {
+			keys = append(keys, k)
+		}
+		slices.Sort(keys)
+
 		// Write each record to a buffer.
 		var buf strings.Builder
-		// Sort keys for deterministic ordering.
-		for _, k := range slices.Sorted(maps.Keys(paxHdrs)) {
+		for _, k := range keys {
 			rec, err := formatPAXRecord(k, paxHdrs[k])
 			if err != nil {
 				return err
@@ -408,37 +413,25 @@ func (tw *Writer) AddFS(fsys fs.FS) error {
 		if err != nil {
 			return err
 		}
-		if name == "." {
+		if d.IsDir() {
 			return nil
 		}
 		info, err := d.Info()
 		if err != nil {
 			return err
 		}
-		linkTarget := ""
-		if typ := d.Type(); typ == fs.ModeSymlink {
-			var err error
-			linkTarget, err = fs.ReadLink(fsys, name)
-			if err != nil {
-				return err
-			}
-		} else if !typ.IsRegular() && typ != fs.ModeDir {
+		// TODO(#49580): Handle symlinks when fs.ReadLinkFS is available.
+		if !info.Mode().IsRegular() {
 			return errors.New("tar: cannot add non-regular file")
 		}
-		h, err := FileInfoHeader(info, linkTarget)
+		h, err := FileInfoHeader(info, "")
 		if err != nil {
 			return err
 		}
 		h.Name = name
-		if d.IsDir() {
-			h.Name += "/"
-		}
 		if err := tw.WriteHeader(h); err != nil {
 			return err
 		}
-		if !d.Type().IsRegular() {
-			return nil
-		}
 		f, err := fsys.Open(name)
 		if err != nil {
 			return err
@@ -675,7 +668,6 @@ func (sw *sparseFileWriter) ReadFrom(r io.Reader) (n int64, err error) {
 func (sw sparseFileWriter) logicalRemaining() int64 {
 	return sw.sp[len(sw.sp)-1].endOffset() - sw.pos
 }
-
 func (sw sparseFileWriter) physicalRemaining() int64 {
 	return sw.fw.physicalRemaining()
 }

src/archive/tar/writer_test.go

@@ -10,11 +10,10 @@ import (
 	"errors"
 	"io"
 	"io/fs"
-	"maps"
 	"os"
 	"path"
+	"reflect"
 	"slices"
-	"sort"
 	"strings"
 	"testing"
 	"testing/fstest"
@@ -703,7 +702,7 @@ func TestPaxXattrs(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	if !maps.Equal(hdr.Xattrs, xattrs) {
+	if !reflect.DeepEqual(hdr.Xattrs, xattrs) {
 		t.Fatalf("xattrs did not survive round trip: got %+v, want %+v",
 			hdr.Xattrs, xattrs)
 	}
@@ -1339,41 +1338,29 @@ func TestFileWriter(t *testing.T) {
 
 func TestWriterAddFS(t *testing.T) {
 	fsys := fstest.MapFS{
-		"emptyfolder":          {Mode: 0o755 | os.ModeDir},
 		"file.go":              {Data: []byte("hello")},
 		"subfolder/another.go": {Data: []byte("world")},
-		"symlink.go":           {Mode: 0o777 | os.ModeSymlink, Data: []byte("file.go")},
-		// Notably missing here is the "subfolder" directory. This makes sure even
-		// if we don't have a subfolder directory listed.
 	}
 	var buf bytes.Buffer
 	tw := NewWriter(&buf)
 	if err := tw.AddFS(fsys); err != nil {
 		t.Fatal(err)
 	}
-	if err := tw.Close(); err != nil {
-		t.Fatal(err)
-	}
-
-	// Add subfolder into fsys to match what we'll read from the tar.
-	fsys["subfolder"] = &fstest.MapFile{Mode: 0o555 | os.ModeDir}
 
 	// Test that we can get the files back from the archive
 	tr := NewReader(&buf)
 
-	names := make([]string, 0, len(fsys))
-	for name := range fsys {
-		names = append(names, name)
-	}
-	sort.Strings(names)
-
-	entriesLeft := len(fsys)
-	for _, name := range names {
-		entriesLeft--
-
-		entryInfo, err := fsys.Lstat(name)
+	entries, err := fsys.ReadDir(".")
 	if err != nil {
-			t.Fatalf("getting entry info error: %v", err)
+		t.Fatal(err)
+	}
+
+	var curfname string
+	for _, entry := range entries {
+		curfname = entry.Name()
+		if entry.IsDir() {
+			curfname += "/"
+			continue
 		}
 		hdr, err := tr.Next()
 		if err == io.EOF {
@@ -1383,43 +1370,23 @@ func TestWriterAddFS(t *testing.T) {
 			t.Fatal(err)
 		}
 
-		tmpName := name
-		if entryInfo.IsDir() {
-			tmpName += "/"
-		}
-		if hdr.Name != tmpName {
-			t.Errorf("test fs has filename %v; archive header has %v",
-				name, hdr.Name)
-		}
-
-		if entryInfo.Mode() != hdr.FileInfo().Mode() {
-			t.Errorf("%s: test fs has mode %v; archive header has %v",
-				name, entryInfo.Mode(), hdr.FileInfo().Mode())
-		}
-
-		switch entryInfo.Mode().Type() {
-		case fs.ModeDir:
-			// No additional checks necessary.
-		case fs.ModeSymlink:
-			origtarget := string(fsys[name].Data)
-			if hdr.Linkname != origtarget {
-				t.Fatalf("test fs has link content %s; archive header %v", origtarget, hdr.Linkname)
-			}
-		default:
 		data, err := io.ReadAll(tr)
 		if err != nil {
 			t.Fatal(err)
 		}
-			origdata := fsys[name].Data
+
+		if hdr.Name != curfname {
+			t.Fatalf("got filename %v, want %v",
+				curfname, hdr.Name)
+		}
+
+		origdata := fsys[curfname].Data
 		if string(data) != string(origdata) {
-				t.Fatalf("test fs has file content %v; archive header has %v", origdata, data)
+			t.Fatalf("got file content %v, want %v",
+				data, origdata)
 		}
 	}
 }
-	if entriesLeft > 0 {
-		t.Fatalf("not all entries are in the archive")
-	}
-}
 
 func TestWriterAddFSNonRegularFiles(t *testing.T) {
 	fsys := fstest.MapFS{

src/archive/zip/reader.go

@@ -8,7 +8,6 @@ import (
 	"bufio"
 	"encoding/binary"
 	"errors"
-	"fmt"
 	"hash"
 	"hash/crc32"
 	"internal/godebug"
@@ -805,9 +804,6 @@ func toValidName(name string) string {
 
 func (r *Reader) initFileList() {
 	r.fileListOnce.Do(func() {
-		// Preallocate the minimum size of the index.
-		// We may also synthesize additional directory entries.
-		r.fileList = make([]fileListEntry, 0, len(r.File))
 		// files and knownDirs map from a file/directory name
 		// to an index into the r.fileList entry that we are
 		// building. They are used to mark duplicate entries.
@@ -906,8 +902,14 @@ func (r *Reader) Open(name string) (fs.File, error) {
 }
 
 func split(name string) (dir, elem string, isDir bool) {
-	name, isDir = strings.CutSuffix(name, "/")
-	i := strings.LastIndexByte(name, '/')
+	if len(name) > 0 && name[len(name)-1] == '/' {
+		isDir = true
+		name = name[:len(name)-1]
+	}
+	i := len(name) - 1
+	for i >= 0 && name[i] != '/' {
+		i--
+	}
 	if i < 0 {
 		return ".", name, isDir
 	}
@@ -989,12 +991,6 @@ func (d *openDir) ReadDir(count int) ([]fs.DirEntry, error) {
 		s, err := d.files[d.offset+i].stat()
 		if err != nil {
 			return nil, err
-		} else if s.Name() == "." || !fs.ValidPath(s.Name()) {
-			return nil, &fs.PathError{
-				Op:   "readdir",
-				Path: d.e.name,
-				Err:  fmt.Errorf("invalid file name: %v", d.files[d.offset+i].name),
-			}
 		}
 		list[i] = s
 	}

src/archive/zip/reader_test.go

@@ -8,14 +8,13 @@ import (
 	"bytes"
 	"encoding/binary"
 	"encoding/hex"
-	"errors"
 	"internal/obscuretestdata"
 	"io"
 	"io/fs"
 	"os"
 	"path/filepath"
+	"reflect"
 	"regexp"
-	"slices"
 	"strings"
 	"testing"
 	"testing/fstest"
@@ -1275,56 +1274,13 @@ func TestFSWalk(t *testing.T) {
 			} else if !test.wantErr && sawErr {
 				t.Error("unexpected error")
 			}
-			if test.want != nil && !slices.Equal(files, test.want) {
+			if test.want != nil && !reflect.DeepEqual(files, test.want) {
 				t.Errorf("got %v want %v", files, test.want)
 			}
 		})
 	}
 }
 
-func TestFSWalkBadFile(t *testing.T) {
-	t.Parallel()
-
-	var buf bytes.Buffer
-	zw := NewWriter(&buf)
-	hdr := &FileHeader{Name: "."}
-	hdr.SetMode(fs.ModeDir | 0o755)
-	w, err := zw.CreateHeader(hdr)
-	if err != nil {
-		t.Fatalf("create zip header: %v", err)
-	}
-	_, err = w.Write([]byte("some data"))
-	if err != nil {
-		t.Fatalf("write zip contents: %v", err)
-
-	}
-	err = zw.Close()
-	if err != nil {
-		t.Fatalf("close zip writer: %v", err)
-
-	}
-
-	zr, err := NewReader(bytes.NewReader(buf.Bytes()), int64(buf.Len()))
-	if err != nil {
-		t.Fatalf("create zip reader: %v", err)
-
-	}
-	var count int
-	var errRepeat = errors.New("repeated call to path")
-	err = fs.WalkDir(zr, ".", func(p string, d fs.DirEntry, err error) error {
-		count++
-		if count > 2 { // once for directory read, once for the error
-			return errRepeat
-		}
-		return err
-	})
-	if err == nil {
-		t.Fatalf("expected error from invalid file name")
-	} else if errors.Is(err, errRepeat) {
-		t.Fatal(err)
-	}
-}
-
 func TestFSModTime(t *testing.T) {
 	t.Parallel()
 	z, err := OpenReader("testdata/subdir.zip")
@@ -1624,7 +1580,7 @@ func TestCVE202141772(t *testing.T) {
 			t.Errorf("Opening %q with fs.FS API succeeded", f.Name)
 		}
 	}
-	if !slices.Equal(names, entryNames) {
+	if !reflect.DeepEqual(names, entryNames) {
 		t.Errorf("Unexpected file entries: %q", names)
 	}
 	if _, err := r.Open(""); err == nil {
@@ -1737,7 +1693,7 @@ func TestInsecurePaths(t *testing.T) {
 		for _, f := range zr.File {
 			gotPaths = append(gotPaths, f.Name)
 		}
-		if !slices.Equal(gotPaths, []string{path}) {
+		if !reflect.DeepEqual(gotPaths, []string{path}) {
 			t.Errorf("NewReader for archive with file %q: got files %q", path, gotPaths)
 			continue
 		}
@@ -1762,7 +1718,7 @@ func TestDisableInsecurePathCheck(t *testing.T) {
 	for _, f := range zr.File {
 		gotPaths = append(gotPaths, f.Name)
 	}
-	if want := []string{name}; !slices.Equal(gotPaths, want) {
+	if want := []string{name}; !reflect.DeepEqual(gotPaths, want) {
 		t.Errorf("NewReader with zipinsecurepath=1: got files %q, want %q", gotPaths, want)
 	}
 }

src/archive/zip/writer.go

@@ -505,14 +505,14 @@ func (w *Writer) AddFS(fsys fs.FS) error {
 		if err != nil {
 			return err
 		}
-		if name == "." {
+		if d.IsDir() {
 			return nil
 		}
 		info, err := d.Info()
 		if err != nil {
 			return err
 		}
-		if !d.IsDir() && !info.Mode().IsRegular() {
+		if !info.Mode().IsRegular() {
 			return errors.New("zip: cannot add non-regular file")
 		}
 		h, err := FileInfoHeader(info)
@@ -520,17 +520,11 @@ func (w *Writer) AddFS(fsys fs.FS) error {
 			return err
 		}
 		h.Name = name
-		if d.IsDir() {
-			h.Name += "/"
-		}
 		h.Method = Deflate
 		fw, err := w.CreateHeader(h)
 		if err != nil {
 			return err
 		}
-		if d.IsDir() {
-			return nil
-		}
 		f, err := fsys.Open(name)
 		if err != nil {
 			return err

src/archive/zip/writer_test.go

@@ -108,7 +108,7 @@ func TestWriter(t *testing.T) {
 
 // TestWriterComment is test for EOCD comment read/write.
 func TestWriterComment(t *testing.T) {
-	tests := []struct {
+	var tests = []struct {
 		comment string
 		ok      bool
 	}{
@@ -158,7 +158,7 @@ func TestWriterComment(t *testing.T) {
 }
 
 func TestWriterUTF8(t *testing.T) {
-	utf8Tests := []struct {
+	var utf8Tests = []struct {
 		name    string
 		comment string
 		nonUTF8 bool
@@ -619,32 +619,32 @@ func TestWriterAddFS(t *testing.T) {
 	buf := new(bytes.Buffer)
 	w := NewWriter(buf)
 	tests := []WriteTest{
-		{Name: "emptyfolder", Mode: 0o755 | os.ModeDir},
-		{Name: "file.go", Data: []byte("hello"), Mode: 0644},
-		{Name: "subfolder/another.go", Data: []byte("world"), Mode: 0644},
-		// Notably missing here is the "subfolder" directory. This makes sure even
-		// if we don't have a subfolder directory listed.
+		{
+			Name: "file.go",
+			Data: []byte("hello"),
+			Mode: 0644,
+		},
+		{
+			Name: "subfolder/another.go",
+			Data: []byte("world"),
+			Mode: 0644,
+		},
 	}
 	err := w.AddFS(writeTestsToFS(tests))
 	if err != nil {
 		t.Fatal(err)
 	}
+
 	if err := w.Close(); err != nil {
 		t.Fatal(err)
 	}
 
-	// Add subfolder into fsys to match what we'll read from the zip.
-	tests = append(tests[:2:2], WriteTest{Name: "subfolder", Mode: 0o555 | os.ModeDir}, tests[2])
-
 	// read it back
 	r, err := NewReader(bytes.NewReader(buf.Bytes()), int64(buf.Len()))
 	if err != nil {
 		t.Fatal(err)
 	}
 	for i, wt := range tests {
-		if wt.Mode.IsDir() {
-			wt.Name += "/"
-		}
 		testReadFile(t, r.File[i], &wt)
 	}
 }

src/bufio/bufio.go

@@ -29,9 +29,6 @@ var (
 // Buffered input.
 
 // Reader implements buffering for an io.Reader object.
-// A new Reader is created by calling [NewReader] or [NewReaderSize];
-// alternatively the zero value of a Reader may be used after calling [Reset]
-// on it.
 type Reader struct {
 	buf          []byte
 	rd           io.Reader // reader provided by the client
@@ -133,10 +130,9 @@ func (b *Reader) readErr() error {
 }
 
 // Peek returns the next n bytes without advancing the reader. The bytes stop
-// being valid at the next read call. If necessary, Peek will read more bytes
-// into the buffer in order to make n bytes available. If Peek returns fewer
-// than n bytes, it also returns an error explaining why the read is short.
-// The error is [ErrBufferFull] if n is larger than b's buffer size.
+// being valid at the next read call. If Peek returns fewer than n bytes, it
+// also returns an error explaining why the read is short. The error is
+// [ErrBufferFull] if n is larger than b's buffer size.
 //
 // Calling Peek prevents a [Reader.UnreadByte] or [Reader.UnreadRune] call from succeeding
 // until the next read operation.
@@ -519,12 +515,10 @@ func (b *Reader) WriteTo(w io.Writer) (n int64, err error) {
 	b.lastByte = -1
 	b.lastRuneSize = -1
 
-	if b.r < b.w {
 	n, err = b.writeBuf(w)
 	if err != nil {
 		return
 	}
-	}
 
 	if r, ok := b.rd.(io.WriterTo); ok {
 		m, err := r.WriteTo(w)

src/bufio/bufio_test.go

@@ -9,7 +9,6 @@ import (
 	"bytes"
 	"errors"
 	"fmt"
-	"internal/asan"
 	"io"
 	"math/rand"
 	"strconv"
@@ -586,9 +585,6 @@ func TestWriteInvalidRune(t *testing.T) {
 }
 
 func TestReadStringAllocs(t *testing.T) {
-	if asan.Enabled {
-		t.Skip("test allocates more with -asan; see #70079")
-	}
 	r := strings.NewReader("       foo       foo        42        42        42        42        42        42        42        42       4.2       4.2       4.2       4.2\n")
 	buf := NewReader(r)
 	allocs := testing.AllocsPerRun(100, func() {
@@ -640,7 +636,7 @@ func TestWriter(t *testing.T) {
 			for l := 0; l < len(written); l++ {
 				if written[l] != data[l] {
 					t.Errorf("wrong bytes written")
-					t.Errorf("want=%q", data[:len(written)])
+					t.Errorf("want=%q", data[0:len(written)])
 					t.Errorf("have=%q", written)
 				}
 			}
@@ -939,6 +935,7 @@ func (t *testReader) Read(buf []byte) (n int, err error) {
 }
 
 func testReadLine(t *testing.T, input []byte) {
+	//for stride := 1; stride < len(input); stride++ {
 	for stride := 1; stride < 2; stride++ {
 		done := 0
 		reader := testReader{input, stride}
@@ -1149,7 +1146,7 @@ func (w errorWriterToTest) Write(p []byte) (int, error) {
 var errorWriterToTests = []errorWriterToTest{
 	{1, 0, nil, io.ErrClosedPipe, io.ErrClosedPipe},
 	{0, 1, io.ErrClosedPipe, nil, io.ErrClosedPipe},
-	{0, 0, io.ErrUnexpectedEOF, io.ErrClosedPipe, io.ErrUnexpectedEOF},
+	{0, 0, io.ErrUnexpectedEOF, io.ErrClosedPipe, io.ErrClosedPipe},
 	{0, 1, io.EOF, nil, nil},
 }
 

src/bufio/example_test.go

@@ -33,33 +33,6 @@ func ExampleWriter_AvailableBuffer() {
 	// Output: 1 2 3 4
 }
 
-// ExampleWriter_ReadFrom demonstrates how to use the ReadFrom method of Writer.
-func ExampleWriter_ReadFrom() {
-	var buf bytes.Buffer
-	writer := bufio.NewWriter(&buf)
-
-	data := "Hello, world!\nThis is a ReadFrom example."
-	reader := strings.NewReader(data)
-
-	n, err := writer.ReadFrom(reader)
-	if err != nil {
-		fmt.Println("ReadFrom Error:", err)
-		return
-	}
-
-	if err = writer.Flush(); err != nil {
-		fmt.Println("Flush Error:", err)
-		return
-	}
-
-	fmt.Println("Bytes written:", n)
-	fmt.Println("Buffer contents:", buf.String())
-	// Output:
-	// Bytes written: 41
-	// Buffer contents: Hello, world!
-	// This is a ReadFrom example.
-}
-
 // The simplest use of a Scanner, to read standard input as a set of lines.
 func ExampleScanner_lines() {
 	scanner := bufio.NewScanner(os.Stdin)

src/bufio/net_test.go

@@ -1,96 +0,0 @@
-// Copyright 2025 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.
-
-//go:build unix
-
-package bufio_test
-
-import (
-	"bufio"
-	"io"
-	"net"
-	"path/filepath"
-	"strings"
-	"sync"
-	"testing"
-)
-
-// TestCopyUnixpacket tests that we can use bufio when copying
-// across a unixpacket socket. This used to fail due to an unnecessary
-// empty Write call that was interpreted as an EOF.
-func TestCopyUnixpacket(t *testing.T) {
-	tmpDir := t.TempDir()
-	socket := filepath.Join(tmpDir, "unixsock")
-
-	// Start a unixpacket server.
-	addr := &net.UnixAddr{
-		Name: socket,
-		Net:  "unixpacket",
-	}
-	server, err := net.ListenUnix("unixpacket", addr)
-	if err != nil {
-		t.Skipf("skipping test because opening a unixpacket socket failed: %v", err)
-	}
-
-	// Start a goroutine for the server to accept one connection
-	// and read all the data sent on the connection,
-	// reporting the number of bytes read on ch.
-	ch := make(chan int, 1)
-	var wg sync.WaitGroup
-	wg.Add(1)
-	go func() {
-		defer wg.Done()
-
-		tot := 0
-		defer func() {
-			ch <- tot
-		}()
-
-		serverConn, err := server.Accept()
-		if err != nil {
-			t.Error(err)
-			return
-		}
-
-		buf := make([]byte, 1024)
-		for {
-			n, err := serverConn.Read(buf)
-			tot += n
-			if err == io.EOF {
-				return
-			}
-			if err != nil {
-				t.Error(err)
-				return
-			}
-		}
-	}()
-
-	clientConn, err := net.DialUnix("unixpacket", nil, addr)
-	if err != nil {
-		// Leaves the server goroutine hanging. Oh well.
-		t.Fatal(err)
-	}
-
-	defer wg.Wait()
-	defer clientConn.Close()
-
-	const data = "data"
-	r := bufio.NewReader(strings.NewReader(data))
-	n, err := io.Copy(clientConn, r)
-	if err != nil {
-		t.Fatal(err)
-	}
-
-	if n != int64(len(data)) {
-		t.Errorf("io.Copy returned %d, want %d", n, len(data))
-	}
-
-	clientConn.Close()
-	tot := <-ch
-
-	if tot != len(data) {
-		t.Errorf("server read %d, want %d", tot, len(data))
-	}
-}

src/builtin/builtin.go

@@ -162,11 +162,11 @@ func delete(m map[Type]Type1, key Type)
 
 // The len built-in function returns the length of v, according to its type:
 //
-//   - Array: the number of elements in v.
-//   - Pointer to array: the number of elements in *v (even if v is nil).
-//   - Slice, or map: the number of elements in v; if v is nil, len(v) is zero.
-//   - String: the number of bytes in v.
-//   - Channel: the number of elements queued (unread) in the channel buffer;
+//	Array: the number of elements in v.
+//	Pointer to array: the number of elements in *v (even if v is nil).
+//	Slice, or map: the number of elements in v; if v is nil, len(v) is zero.
+//	String: the number of bytes in v.
+//	Channel: the number of elements queued (unread) in the channel buffer;
 //	         if v is nil, len(v) is zero.
 //
 // For some arguments, such as a string literal or a simple array expression, the
@@ -176,11 +176,11 @@ func len(v Type) int
 
 // The cap built-in function returns the capacity of v, according to its type:
 //
-//   - Array: the number of elements in v (same as len(v)).
-//   - Pointer to array: the number of elements in *v (same as len(v)).
-//   - Slice: the maximum length the slice can reach when resliced;
+//	Array: the number of elements in v (same as len(v)).
+//	Pointer to array: the number of elements in *v (same as len(v)).
+//	Slice: the maximum length the slice can reach when resliced;
 //	if v is nil, cap(v) is zero.
-//   - Channel: the channel buffer capacity, in units of elements;
+//	Channel: the channel buffer capacity, in units of elements;
 //	if v is nil, cap(v) is zero.
 //
 // For some arguments, such as a simple array expression, the result can be a
@@ -194,16 +194,16 @@ func cap(v Type) int
 // argument, not a pointer to it. The specification of the result depends on
 // the type:
 //
-//   - Slice: The size specifies the length. The capacity of the slice is
+//	Slice: The size specifies the length. The capacity of the slice is
 //	equal to its length. A second integer argument may be provided to
 //	specify a different capacity; it must be no smaller than the
 //	length. For example, make([]int, 0, 10) allocates an underlying array
 //	of size 10 and returns a slice of length 0 and capacity 10 that is
 //	backed by this underlying array.
-//   - Map: An empty map is allocated with enough space to hold the
+//	Map: An empty map is allocated with enough space to hold the
 //	specified number of elements. The size may be omitted, in which case
 //	a small starting size is allocated.
-//   - Channel: The channel's buffer is initialized with the specified
+//	Channel: The channel's buffer is initialized with the specified
 //	buffer capacity. If zero, or the size is omitted, the channel is
 //	unbuffered.
 func make(t Type, size ...IntegerType) Type
@@ -247,7 +247,7 @@ func imag(c ComplexType) FloatType
 // to the zero value of the respective element type. If the argument
 // type is a type parameter, the type parameter's type set must
 // contain only map or slice types, and clear performs the operation
-// implied by the type argument. If t is nil, clear is a no-op.
+// implied by the type argument.
 func clear[T ~[]Type | ~map[Type]Type1](t T)
 
 // The close built-in function closes a channel, which must be either

src/bytes/buffer.go

@@ -247,8 +247,8 @@ func growSlice(b []byte, n int) []byte {
 		c = 2 * cap(b)
 	}
 	b2 := append([]byte(nil), make([]byte, c)...)
-	i := copy(b2, b)
-	return b2[:i]
+	copy(b2, b)
+	return b2[:len(b)]
 }
 
 // WriteTo writes data to w until the buffer is drained or an error occurs.

src/bytes/buffer_test.go

@@ -213,7 +213,7 @@ func TestLargeByteWrites(t *testing.T) {
 func TestLargeStringReads(t *testing.T) {
 	var buf Buffer
 	for i := 3; i < 30; i += 3 {
-		s := fillString(t, "TestLargeReads (1)", &buf, "", 5, testString[:len(testString)/i])
+		s := fillString(t, "TestLargeReads (1)", &buf, "", 5, testString[0:len(testString)/i])
 		empty(t, "TestLargeReads (2)", &buf, s, make([]byte, len(testString)))
 	}
 	check(t, "TestLargeStringReads (3)", &buf, "")
@@ -222,7 +222,7 @@ func TestLargeStringReads(t *testing.T) {
 func TestLargeByteReads(t *testing.T) {
 	var buf Buffer
 	for i := 3; i < 30; i += 3 {
-		s := fillBytes(t, "TestLargeReads (1)", &buf, "", 5, testBytes[:len(testBytes)/i])
+		s := fillBytes(t, "TestLargeReads (1)", &buf, "", 5, testBytes[0:len(testBytes)/i])
 		empty(t, "TestLargeReads (2)", &buf, s, make([]byte, len(testString)))
 	}
 	check(t, "TestLargeByteReads (3)", &buf, "")
@@ -274,7 +274,7 @@ func TestNil(t *testing.T) {
 func TestReadFrom(t *testing.T) {
 	var buf Buffer
 	for i := 3; i < 30; i += 3 {
-		s := fillBytes(t, "TestReadFrom (1)", &buf, "", 5, testBytes[:len(testBytes)/i])
+		s := fillBytes(t, "TestReadFrom (1)", &buf, "", 5, testBytes[0:len(testBytes)/i])
 		var b Buffer
 		b.ReadFrom(&buf)
 		empty(t, "TestReadFrom (2)", &b, s, make([]byte, len(testString)))
@@ -337,7 +337,7 @@ func TestReadFromNegativeReader(t *testing.T) {
 func TestWriteTo(t *testing.T) {
 	var buf Buffer
 	for i := 3; i < 30; i += 3 {
-		s := fillBytes(t, "TestWriteTo (1)", &buf, "", 5, testBytes[:len(testBytes)/i])
+		s := fillBytes(t, "TestWriteTo (1)", &buf, "", 5, testBytes[0:len(testBytes)/i])
 		var b Buffer
 		buf.WriteTo(&b)
 		empty(t, "TestWriteTo (2)", &b, s, make([]byte, len(testString)))

src/bytes/bytes.go

@@ -8,7 +8,6 @@ package bytes
 
 import (
 	"internal/bytealg"
-	"math/bits"
 	"unicode"
 	"unicode/utf8"
 	_ "unsafe" // for linkname
@@ -137,7 +136,6 @@ func LastIndexByte(s []byte, c byte) int {
 // If r is [utf8.RuneError], it returns the first instance of any
 // invalid UTF-8 byte sequence.
 func IndexRune(s []byte, r rune) int {
-	const haveFastIndex = bytealg.MaxBruteForce > 0
 	switch {
 	case 0 <= r && r < utf8.RuneSelf:
 		return IndexByte(s, byte(r))
@@ -153,64 +151,9 @@ func IndexRune(s []byte, r rune) int {
 	case !utf8.ValidRune(r):
 		return -1
 	default:
-		// Search for rune r using the last byte of its UTF-8 encoded form.
-		// The distribution of the last byte is more uniform compared to the
-		// first byte which has a 78% chance of being [240, 243, 244].
 		var b [utf8.UTFMax]byte
 		n := utf8.EncodeRune(b[:], r)
-		last := n - 1
-		i := last
-		fails := 0
-		for i < len(s) {
-			if s[i] != b[last] {
-				o := IndexByte(s[i+1:], b[last])
-				if o < 0 {
-					return -1
-				}
-				i += o + 1
-			}
-			// Step backwards comparing bytes.
-			for j := 1; j < n; j++ {
-				if s[i-j] != b[last-j] {
-					goto next
-				}
-			}
-			return i - last
-		next:
-			fails++
-			i++
-			if (haveFastIndex && fails > bytealg.Cutover(i)) && i < len(s) ||
-				(!haveFastIndex && fails >= 4+i>>4 && i < len(s)) {
-				goto fallback
-			}
-		}
-		return -1
-
-	fallback:
-		// Switch to bytealg.Index, if available, or a brute force search when
-		// IndexByte returns too many false positives.
-		if haveFastIndex {
-			if j := bytealg.Index(s[i-last:], b[:n]); j >= 0 {
-				return i + j - last
-			}
-		} else {
-			// If bytealg.Index is not available a brute force search is
-			// ~1.5-3x faster than Rabin-Karp since n is small.
-			c0 := b[last]
-			c1 := b[last-1] // There are at least 2 chars to match
-		loop:
-			for ; i < len(s); i++ {
-				if s[i] == c0 && s[i-1] == c1 {
-					for k := 2; k < n; k++ {
-						if s[i-k] != b[last-k] {
-							continue loop
-						}
-					}
-					return i - last
-				}
-			}
-		}
-		return -1
+		return Index(s, b[:n])
 	}
 }
 
@@ -451,9 +394,7 @@ var asciiSpace = [256]uint8{'\t': 1, '\n': 1, '\v': 1, '\f': 1, '\r': 1, ' ': 1}
 // Fields interprets s as a sequence of UTF-8-encoded code points.
 // It splits the slice s around each instance of one or more consecutive white space
 // characters, as defined by [unicode.IsSpace], returning a slice of subslices of s or an
-// empty slice if s contains only white space. Every element of the returned slice is
-// non-empty. Unlike [Split], leading and trailing runs of white space characters
-// are discarded.
+// empty slice if s contains only white space.
 func Fields(s []byte) [][]byte {
 	// First count the fields.
 	// This is an exact count if s is ASCII, otherwise it is an approximation.
@@ -507,9 +448,7 @@ func Fields(s []byte) [][]byte {
 // FieldsFunc interprets s as a sequence of UTF-8-encoded code points.
 // It splits the slice s at each run of code points c satisfying f(c) and
 // returns a slice of subslices of s. If all code points in s satisfy f(c), or
-// len(s) == 0, an empty slice is returned. Every element of the returned slice is
-// non-empty. Unlike [SplitFunc], leading and trailing runs of code points
-// satisfying f(c) are discarded.
+// len(s) == 0, an empty slice is returned.
 //
 // FieldsFunc makes no guarantees about the order in which it calls f(c)
 // and assumes that f always returns the same value for a given c.
@@ -596,7 +535,7 @@ func Join(s [][]byte, sep []byte) []byte {
 
 // HasPrefix reports whether the byte slice s begins with prefix.
 func HasPrefix(s, prefix []byte) bool {
-	return len(s) >= len(prefix) && Equal(s[:len(prefix)], prefix)
+	return len(s) >= len(prefix) && Equal(s[0:len(prefix)], prefix)
 }
 
 // HasSuffix reports whether the byte slice s ends with suffix.
@@ -655,11 +594,10 @@ func Repeat(b []byte, count int) []byte {
 	if count < 0 {
 		panic("bytes: negative Repeat count")
 	}
-	hi, lo := bits.Mul(uint(len(b)), uint(count))
-	if hi > 0 || lo > uint(maxInt) {
+	if len(b) > maxInt/count {
 		panic("bytes: Repeat output length overflow")
 	}
-	n := int(lo) // lo = len(b) * count
+	n := len(b) * count
 
 	if len(b) == 0 {
 		return []byte{}
@@ -686,7 +624,10 @@ func Repeat(b []byte, count int) []byte {
 	nb := bytealg.MakeNoZero(n)[:n:n]
 	bp := copy(nb, b)
 	for bp < n {
-		chunk := min(bp, chunkMax)
+		chunk := bp
+		if chunk > chunkMax {
+			chunk = chunkMax
+		}
 		bp += copy(nb[bp:], nb[:chunk])
 	}
 	return nb
@@ -1192,23 +1133,20 @@ func Replace(s, old, new []byte, n int) []byte {
 	t := make([]byte, len(s)+n*(len(new)-len(old)))
 	w := 0
 	start := 0
-	if len(old) > 0 {
-		for range n {
-			j := start + Index(s[start:], old)
+	for i := 0; i < n; i++ {
+		j := start
+		if len(old) == 0 {
+			if i > 0 {
+				_, wid := utf8.DecodeRune(s[start:])
+				j += wid
+			}
+		} else {
+			j += Index(s[start:], old)
+		}
 		w += copy(t[w:], s[start:j])
 		w += copy(t[w:], new)
 		start = j + len(old)
 	}
-	} else { // len(old) == 0
-		w += copy(t[w:], new)
-		for range n - 1 {
-			_, wid := utf8.DecodeRune(s[start:])
-			j := start + wid
-			w += copy(t[w:], s[start:j])
-			w += copy(t[w:], new)
-			start = j
-		}
-	}
 	w += copy(t[w:], s[start:])
 	return t[0:w]
 }

src/bytes/bytes_test.go

@@ -7,12 +7,10 @@ package bytes_test
 import (
 	. "bytes"
 	"fmt"
-	"internal/asan"
 	"internal/testenv"
-	"iter"
 	"math"
 	"math/rand"
-	"slices"
+	"reflect"
 	"strings"
 	"testing"
 	"unicode"
@@ -20,6 +18,18 @@ import (
 	"unsafe"
 )
 
+func eq(a, b []string) bool {
+	if len(a) != len(b) {
+		return false
+	}
+	for i := 0; i < len(a); i++ {
+		if a[i] != b[i] {
+			return false
+		}
+	}
+	return true
+}
+
 func sliceOfString(s [][]byte) []string {
 	result := make([]string, len(s))
 	for i, v := range s {
@@ -28,37 +38,6 @@ func sliceOfString(s [][]byte) []string {
 	return result
 }
 
-func collect(t *testing.T, seq iter.Seq[[]byte]) [][]byte {
-	out := slices.Collect(seq)
-	out1 := slices.Collect(seq)
-	if !slices.Equal(sliceOfString(out), sliceOfString(out1)) {
-		t.Fatalf("inconsistent seq:\n%s\n%s", out, out1)
-	}
-	return out
-}
-
-type LinesTest struct {
-	a string
-	b []string
-}
-
-var linesTests = []LinesTest{
-	{a: "abc\nabc\n", b: []string{"abc\n", "abc\n"}},
-	{a: "abc\r\nabc", b: []string{"abc\r\n", "abc"}},
-	{a: "abc\r\n", b: []string{"abc\r\n"}},
-	{a: "\nabc", b: []string{"\n", "abc"}},
-	{a: "\nabc\n\n", b: []string{"\n", "abc\n", "\n"}},
-}
-
-func TestLines(t *testing.T) {
-	for _, s := range linesTests {
-		result := sliceOfString(slices.Collect(Lines([]byte(s.a))))
-		if !slices.Equal(result, s.b) {
-			t.Errorf(`slices.Collect(Lines(%q)) = %q; want %q`, s.a, result, s.b)
-		}
-	}
-}
-
 // For ease of reading, the test cases use strings that are converted to byte
 // slices before invoking the functions.
 
@@ -198,11 +177,6 @@ var indexTests = []BinOpTest{
 	{"oxoxoxoxoxoxoxoxoxoxoxox", "oy", -1},
 	// test fallback to Rabin-Karp.
 	{"000000000000000000000000000000000000000000000000000000000000000000000001", "0000000000000000000000000000000000000000000000000000000000000000001", 5},
-	// test fallback to IndexRune
-	{"oxoxoxoxoxoxoxoxoxoxox☺", "☺", 22},
-	// invalid UTF-8 byte sequence (must be longer than bytealg.MaxBruteForce to
-	// test that we don't use IndexRune)
-	{"xx0123456789012345678901234567890123456789012345678901234567890120123456789012345678901234567890123456xxx\xed\x9f\xc0", "\xed\x9f\xc0", 105},
 }
 
 var lastIndexTests = []BinOpTest{
@@ -451,31 +425,6 @@ func TestIndexRune(t *testing.T) {
 		{"some_text=some_value", '=', 9},
 		{"☺a", 'a', 3},
 		{"a☻☺b", '☺', 4},
-		{"𠀳𠀗𠀾𠁄𠀧𠁆𠁂𠀫𠀖𠀪𠀲𠀴𠁀𠀨𠀿", '𠀿', 56},
-
-		// 2 bytes
-		{"ӆ", 'ӆ', 0},
-		{"a", 'ӆ', -1},
-		{"  ӆ", 'ӆ', 2},
-		{"  a", 'ӆ', -1},
-		{strings.Repeat("ц", 64) + "ӆ", 'ӆ', 128}, // test cutover
-		{strings.Repeat("ц", 64), 'ӆ', -1},
-
-		// 3 bytes
-		{"Ꚁ", 'Ꚁ', 0},
-		{"a", 'Ꚁ', -1},
-		{"  Ꚁ", 'Ꚁ', 2},
-		{"  a", 'Ꚁ', -1},
-		{strings.Repeat("Ꙁ", 64) + "Ꚁ", 'Ꚁ', 192}, // test cutover
-		{strings.Repeat("Ꙁ", 64) + "Ꚁ", '䚀', -1},  // 'Ꚁ' and '䚀' share the same last two bytes
-
-		// 4 bytes
-		{"𡌀", '𡌀', 0},
-		{"a", '𡌀', -1},
-		{"  𡌀", '𡌀', 2},
-		{"  a", '𡌀', -1},
-		{strings.Repeat("𡋀", 64) + "𡌀", '𡌀', 256}, // test cutover
-		{strings.Repeat("𡋀", 64) + "𡌀", '𣌀', -1},  // '𡌀' and '𣌀' share the same last two bytes
 
 		// RuneError should match any invalid UTF-8 byte sequence.
 		{"<22>", '<27>', 0},
@@ -489,13 +438,6 @@ func TestIndexRune(t *testing.T) {
 		{"a☺b☻c☹d\xe2\x98<39>\xff<66>\xed\xa0\x80", -1, -1},
 		{"a☺b☻c☹d\xe2\x98<39>\xff<66>\xed\xa0\x80", 0xD800, -1}, // Surrogate pair
 		{"a☺b☻c☹d\xe2\x98<39>\xff<66>\xed\xa0\x80", utf8.MaxRune + 1, -1},
-
-		// Test the cutover to bytealg.Index when it is triggered in
-		// the middle of rune that contains consecutive runs of equal bytes.
-		{"aaaaaKKKK\U000bc104", '\U000bc104', 17}, // cutover: (n + 16) / 8
-		{"aaaaaKKKK鄄", '鄄', 17},
-		{"aaKKKKKa\U000bc104", '\U000bc104', 18}, // cutover: 4 + n>>4
-		{"aaKKKKKa鄄", '鄄', 18},
 	}
 	for _, tt := range tests {
 		if got := IndexRune([]byte(tt.in), tt.rune); got != tt.want {
@@ -643,21 +585,6 @@ func BenchmarkIndexRuneASCII(b *testing.B) {
 	benchBytes(b, indexSizes, bmIndexRuneASCII(IndexRune))
 }
 
-func BenchmarkIndexRuneUnicode(b *testing.B) {
-	b.Run("Latin", func(b *testing.B) {
-		// Latin is mostly 1, 2, 3 byte runes.
-		benchBytes(b, indexSizes, bmIndexRuneUnicode(unicode.Latin, 'é'))
-	})
-	b.Run("Cyrillic", func(b *testing.B) {
-		// Cyrillic is mostly 2 and 3 byte runes.
-		benchBytes(b, indexSizes, bmIndexRuneUnicode(unicode.Cyrillic, 'Ꙁ'))
-	})
-	b.Run("Han", func(b *testing.B) {
-		// Han consists only of 3 and 4 byte runes.
-		benchBytes(b, indexSizes, bmIndexRuneUnicode(unicode.Han, '𠀿'))
-	})
-}
-
 func bmIndexRuneASCII(index func([]byte, rune) int) func(b *testing.B, n int) {
 	return func(b *testing.B, n int) {
 		buf := bmbuf[0:n]
@@ -688,61 +615,6 @@ func bmIndexRune(index func([]byte, rune) int) func(b *testing.B, n int) {
 	}
 }
 
-func bmIndexRuneUnicode(rt *unicode.RangeTable, needle rune) func(b *testing.B, n int) {
-	var rs []rune
-	for _, r16 := range rt.R16 {
-		for r := rune(r16.Lo); r <= rune(r16.Hi); r += rune(r16.Stride) {
-			if r != needle {
-				rs = append(rs, rune(r))
-			}
-		}
-	}
-	for _, r32 := range rt.R32 {
-		for r := rune(r32.Lo); r <= rune(r32.Hi); r += rune(r32.Stride) {
-			if r != needle {
-				rs = append(rs, rune(r))
-			}
-		}
-	}
-	// Shuffle the runes so that they are not in descending order.
-	// The sort is deterministic since this is used for benchmarks,
-	// which need to be repeatable.
-	rr := rand.New(rand.NewSource(1))
-	rr.Shuffle(len(rs), func(i, j int) {
-		rs[i], rs[j] = rs[j], rs[i]
-	})
-	uchars := string(rs)
-
-	return func(b *testing.B, n int) {
-		buf := bmbuf[0:n]
-		o := copy(buf, uchars)
-		for o < len(buf) {
-			o += copy(buf[o:], uchars)
-		}
-
-		// Make space for the needle rune at the end of buf.
-		m := utf8.RuneLen(needle)
-		for o := m; o > 0; {
-			_, sz := utf8.DecodeLastRune(buf)
-			copy(buf[len(buf)-sz:], "\x00\x00\x00\x00")
-			buf = buf[:len(buf)-sz]
-			o -= sz
-		}
-		buf = utf8.AppendRune(buf[:n-m], needle)
-
-		n -= m // adjust for rune len
-		for i := 0; i < b.N; i++ {
-			j := IndexRune(buf, needle)
-			if j != n {
-				b.Fatal("bad index", j)
-			}
-		}
-		for i := range buf {
-			buf[i] = '\x00'
-		}
-	}
-}
-
 func BenchmarkEqual(b *testing.B) {
 	b.Run("0", func(b *testing.B) {
 		var buf [4]byte
@@ -936,18 +808,10 @@ func TestSplit(t *testing.T) {
 		}
 
 		result := sliceOfString(a)
-		if !slices.Equal(result, tt.a) {
+		if !eq(result, tt.a) {
 			t.Errorf(`Split(%q, %q, %d) = %v; want %v`, tt.s, tt.sep, tt.n, result, tt.a)
 			continue
 		}
-
-		if tt.n < 0 {
-			b := sliceOfString(slices.Collect(SplitSeq([]byte(tt.s), []byte(tt.sep))))
-			if !slices.Equal(b, tt.a) {
-				t.Errorf(`collect(SplitSeq(%q, %q)) = %v; want %v`, tt.s, tt.sep, b, tt.a)
-			}
-		}
-
 		if tt.n == 0 || len(a) == 0 {
 			continue
 		}
@@ -961,8 +825,8 @@ func TestSplit(t *testing.T) {
 			t.Errorf(`Join(Split(%q, %q, %d), %q) = %q`, tt.s, tt.sep, tt.n, tt.sep, s)
 		}
 		if tt.n < 0 {
-			b := sliceOfString(Split([]byte(tt.s), []byte(tt.sep)))
-			if !slices.Equal(result, b) {
+			b := Split([]byte(tt.s), []byte(tt.sep))
+			if !reflect.DeepEqual(a, b) {
 				t.Errorf("Split disagrees withSplitN(%q, %q, %d) = %v; want %v", tt.s, tt.sep, tt.n, b, a)
 			}
 		}
@@ -1002,18 +866,11 @@ func TestSplitAfter(t *testing.T) {
 		}
 
 		result := sliceOfString(a)
-		if !slices.Equal(result, tt.a) {
+		if !eq(result, tt.a) {
 			t.Errorf(`Split(%q, %q, %d) = %v; want %v`, tt.s, tt.sep, tt.n, result, tt.a)
 			continue
 		}
 
-		if tt.n < 0 {
-			b := sliceOfString(slices.Collect(SplitAfterSeq([]byte(tt.s), []byte(tt.sep))))
-			if !slices.Equal(b, tt.a) {
-				t.Errorf(`collect(SplitAfterSeq(%q, %q)) = %v; want %v`, tt.s, tt.sep, b, tt.a)
-			}
-		}
-
 		if want := tt.a[len(tt.a)-1] + "z"; string(x) != want {
 			t.Errorf("last appended result was %s; want %s", x, want)
 		}
@@ -1023,8 +880,8 @@ func TestSplitAfter(t *testing.T) {
 			t.Errorf(`Join(Split(%q, %q, %d), %q) = %q`, tt.s, tt.sep, tt.n, tt.sep, s)
 		}
 		if tt.n < 0 {
-			b := sliceOfString(SplitAfter([]byte(tt.s), []byte(tt.sep)))
-			if !slices.Equal(result, b) {
+			b := SplitAfter([]byte(tt.s), []byte(tt.sep))
+			if !reflect.DeepEqual(a, b) {
 				t.Errorf("SplitAfter disagrees withSplitAfterN(%q, %q, %d) = %v; want %v", tt.s, tt.sep, tt.n, b, a)
 			}
 		}
@@ -1062,16 +919,11 @@ func TestFields(t *testing.T) {
 		}
 
 		result := sliceOfString(a)
-		if !slices.Equal(result, tt.a) {
+		if !eq(result, tt.a) {
 			t.Errorf("Fields(%q) = %v; want %v", tt.s, a, tt.a)
 			continue
 		}
 
-		result2 := sliceOfString(collect(t, FieldsSeq([]byte(tt.s))))
-		if !slices.Equal(result2, tt.a) {
-			t.Errorf(`collect(FieldsSeq(%q)) = %v; want %v`, tt.s, result2, tt.a)
-		}
-
 		if string(b) != tt.s {
 			t.Errorf("slice changed to %s; want %s", string(b), tt.s)
 		}
@@ -1087,7 +939,7 @@ func TestFieldsFunc(t *testing.T) {
 	for _, tt := range fieldstests {
 		a := FieldsFunc([]byte(tt.s), unicode.IsSpace)
 		result := sliceOfString(a)
-		if !slices.Equal(result, tt.a) {
+		if !eq(result, tt.a) {
 			t.Errorf("FieldsFunc(%q, unicode.IsSpace) = %v; want %v", tt.s, a, tt.a)
 			continue
 		}
@@ -1110,15 +962,10 @@ func TestFieldsFunc(t *testing.T) {
 		}
 
 		result := sliceOfString(a)
-		if !slices.Equal(result, tt.a) {
+		if !eq(result, tt.a) {
 			t.Errorf("FieldsFunc(%q) = %v, want %v", tt.s, a, tt.a)
 		}
 
-		result2 := sliceOfString(collect(t, FieldsFuncSeq([]byte(tt.s), pred)))
-		if !slices.Equal(result2, tt.a) {
-			t.Errorf(`collect(FieldsFuncSeq(%q)) = %v; want %v`, tt.s, result2, tt.a)
-		}
-
 		if string(b) != tt.s {
 			t.Errorf("slice changed to %s; want %s", b, tt.s)
 		}
@@ -1439,6 +1286,18 @@ func TestRepeatCatchesOverflow(t *testing.T) {
 	})
 }
 
+func runesEqual(a, b []rune) bool {
+	if len(a) != len(b) {
+		return false
+	}
+	for i, r := range a {
+		if r != b[i] {
+			return false
+		}
+	}
+	return true
+}
+
 type RunesTest struct {
 	in    string
 	out   []rune
@@ -1459,7 +1318,7 @@ func TestRunes(t *testing.T) {
 	for _, tt := range RunesTests {
 		tin := []byte(tt.in)
 		a := Runes(tin)
-		if !slices.Equal(a, tt.out) {
+		if !runesEqual(a, tt.out) {
 			t.Errorf("Runes(%q) = %v; want %v", tin, a, tt.out)
 			continue
 		}
@@ -1787,20 +1646,9 @@ var ReplaceTests = []ReplaceTest{
 
 func TestReplace(t *testing.T) {
 	for _, tt := range ReplaceTests {
-		var (
-			in  = []byte(tt.in)
-			old = []byte(tt.old)
-			new = []byte(tt.new)
-		)
-		if !asan.Enabled {
-			allocs := testing.AllocsPerRun(10, func() { Replace(in, old, new, tt.n) })
-			if allocs > 1 {
-				t.Errorf("Replace(%q, %q, %q, %d) allocates %.2f objects", tt.in, tt.old, tt.new, tt.n, allocs)
-			}
-		}
-		in = append(in, "<spare>"...)
+		in := append([]byte(tt.in), "<spare>"...)
 		in = in[:len(tt.in)]
-		out := Replace(in, old, new, tt.n)
+		out := Replace(in, []byte(tt.old), []byte(tt.new), tt.n)
 		if s := string(out); s != tt.out {
 			t.Errorf("Replace(%q, %q, %q, %d) = %q, want %q", tt.in, tt.old, tt.new, tt.n, s, tt.out)
 		}
@@ -1808,7 +1656,7 @@ func TestReplace(t *testing.T) {
 			t.Errorf("Replace(%q, %q, %q, %d) didn't copy", tt.in, tt.old, tt.new, tt.n)
 		}
 		if tt.n == -1 {
-			out := ReplaceAll(in, old, new)
+			out := ReplaceAll(in, []byte(tt.old), []byte(tt.new))
 			if s := string(out); s != tt.out {
 				t.Errorf("ReplaceAll(%q, %q, %q) = %q, want %q", tt.in, tt.old, tt.new, s, tt.out)
 			}
@@ -1816,69 +1664,6 @@ func TestReplace(t *testing.T) {
 	}
 }
 
-func FuzzReplace(f *testing.F) {
-	for _, tt := range ReplaceTests {
-		f.Add([]byte(tt.in), []byte(tt.old), []byte(tt.new), tt.n)
-	}
-	f.Fuzz(func(t *testing.T, in, old, new []byte, n int) {
-		differentImpl := func(in, old, new []byte, n int) []byte {
-			var out Buffer
-			if n < 0 {
-				n = math.MaxInt
-			}
-			for i := 0; i < len(in); {
-				if n == 0 {
-					out.Write(in[i:])
-					break
-				}
-				if HasPrefix(in[i:], old) {
-					out.Write(new)
-					i += len(old)
-					n--
-					if len(old) != 0 {
-						continue
-					}
-					if i == len(in) {
-						break
-					}
-				}
-				if len(old) == 0 {
-					_, length := utf8.DecodeRune(in[i:])
-					out.Write(in[i : i+length])
-					i += length
-				} else {
-					out.WriteByte(in[i])
-					i++
-				}
-			}
-			if len(old) == 0 && n != 0 {
-				out.Write(new)
-			}
-			return out.Bytes()
-		}
-		if simple, replace := differentImpl(in, old, new, n), Replace(in, old, new, n); !slices.Equal(simple, replace) {
-			t.Errorf("The two implementations do not match %q != %q for Replace(%q, %q, %q, %d)", simple, replace, in, old, new, n)
-		}
-	})
-}
-
-func BenchmarkReplace(b *testing.B) {
-	for _, tt := range ReplaceTests {
-		desc := fmt.Sprintf("%q %q %q %d", tt.in, tt.old, tt.new, tt.n)
-		var (
-			in  = []byte(tt.in)
-			old = []byte(tt.old)
-			new = []byte(tt.new)
-		)
-		b.Run(desc, func(b *testing.B) {
-			b.ReportAllocs()
-			for b.Loop() {
-				Replace(in, old, new, tt.n)
-			}
-		})
-	}
-}
-
 type TitleTest struct {
 	in, out string
 }
@@ -2259,11 +2044,6 @@ func makeBenchInputHard() []byte {
 var benchInputHard = makeBenchInputHard()
 
 func benchmarkIndexHard(b *testing.B, sep []byte) {
-	n := Index(benchInputHard, sep)
-	if n < 0 {
-		n = len(benchInputHard)
-	}
-	b.SetBytes(int64(n))
 	for i := 0; i < b.N; i++ {
 		Index(benchInputHard, sep)
 	}

src/bytes/example_test.go

@@ -502,10 +502,10 @@ func ExampleTitle() {
 
 func ExampleToTitle() {
 	fmt.Printf("%s\n", bytes.ToTitle([]byte("loud noises")))
-	fmt.Printf("%s\n", bytes.ToTitle([]byte("брат")))
+	fmt.Printf("%s\n", bytes.ToTitle([]byte("хлеб")))
 	// Output:
 	// LOUD NOISES
-	// БРАТ
+	// ХЛЕБ
 }
 
 func ExampleToTitleSpecial() {
@@ -628,93 +628,3 @@ func ExampleToUpperSpecial() {
 	// Original : ahoj vývojári golang
 	// ToUpper : AHOJ VÝVOJÁRİ GOLANG
 }
-
-func ExampleLines() {
-	text := []byte("Hello\nWorld\nGo Programming\n")
-	for line := range bytes.Lines(text) {
-		fmt.Printf("%q\n", line)
-	}
-
-	// Output:
-	// "Hello\n"
-	// "World\n"
-	// "Go Programming\n"
-}
-
-func ExampleSplitSeq() {
-	s := []byte("a,b,c,d")
-	for part := range bytes.SplitSeq(s, []byte(",")) {
-		fmt.Printf("%q\n", part)
-	}
-
-	// Output:
-	// "a"
-	// "b"
-	// "c"
-	// "d"
-}
-
-func ExampleSplitAfterSeq() {
-	s := []byte("a,b,c,d")
-	for part := range bytes.SplitAfterSeq(s, []byte(",")) {
-		fmt.Printf("%q\n", part)
-	}
-
-	// Output:
-	// "a,"
-	// "b,"
-	// "c,"
-	// "d"
-}
-
-func ExampleFieldsSeq() {
-	text := []byte("The quick brown fox")
-	fmt.Println("Split byte slice into fields:")
-	for word := range bytes.FieldsSeq(text) {
-		fmt.Printf("%q\n", word)
-	}
-
-	textWithSpaces := []byte("  lots   of   spaces  ")
-	fmt.Println("\nSplit byte slice with multiple spaces:")
-	for word := range bytes.FieldsSeq(textWithSpaces) {
-		fmt.Printf("%q\n", word)
-	}
-
-	// Output:
-	// Split byte slice into fields:
-	// "The"
-	// "quick"
-	// "brown"
-	// "fox"
-	//
-	// Split byte slice with multiple spaces:
-	// "lots"
-	// "of"
-	// "spaces"
-}
-
-func ExampleFieldsFuncSeq() {
-	text := []byte("The quick brown fox")
-	fmt.Println("Split on whitespace(similar to FieldsSeq):")
-	for word := range bytes.FieldsFuncSeq(text, unicode.IsSpace) {
-		fmt.Printf("%q\n", word)
-	}
-
-	mixedText := []byte("abc123def456ghi")
-	fmt.Println("\nSplit on digits:")
-	for word := range bytes.FieldsFuncSeq(mixedText, unicode.IsDigit) {
-		fmt.Printf("%q\n", word)
-	}
-
-	// Output:
-	// Split on whitespace(similar to FieldsSeq):
-	// "The"
-	// "quick"
-	// "brown"
-	// "fox"
-	//
-	// Split on digits:
-	// "abc"
-	// "def"
-	// "ghi"
-}

src/bytes/iter.go

@@ -1,146 +0,0 @@
-// Copyright 2024 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 bytes
-
-import (
-	"iter"
-	"unicode"
-	"unicode/utf8"
-)
-
-// Lines returns an iterator over the newline-terminated lines in the byte slice s.
-// The lines yielded by the iterator include their terminating newlines.
-// If s is empty, the iterator yields no lines at all.
-// If s does not end in a newline, the final yielded line will not end in a newline.
-// It returns a single-use iterator.
-func Lines(s []byte) iter.Seq[[]byte] {
-	return func(yield func([]byte) bool) {
-		for len(s) > 0 {
-			var line []byte
-			if i := IndexByte(s, '\n'); i >= 0 {
-				line, s = s[:i+1], s[i+1:]
-			} else {
-				line, s = s, nil
-			}
-			if !yield(line[:len(line):len(line)]) {
-				return
-			}
-		}
-	}
-}
-
-// explodeSeq returns an iterator over the runes in s.
-func explodeSeq(s []byte, yield func([]byte) bool) {
-	for len(s) > 0 {
-		_, size := utf8.DecodeRune(s)
-		if !yield(s[:size:size]) {
-			return
-		}
-		s = s[size:]
-	}
-}
-
-// splitSeq is SplitSeq or SplitAfterSeq, configured by how many
-// bytes of sep to include in the results (none or all).
-func splitSeq(s, sep []byte, sepSave int) iter.Seq[[]byte] {
-	return func(yield func([]byte) bool) {
-		if len(sep) == 0 {
-			explodeSeq(s, yield)
-			return
-		}
-		for {
-			i := Index(s, sep)
-			if i < 0 {
-				break
-			}
-			frag := s[:i+sepSave]
-			if !yield(frag[:len(frag):len(frag)]) {
-				return
-			}
-			s = s[i+len(sep):]
-		}
-		yield(s[:len(s):len(s)])
-	}
-}
-
-// SplitSeq returns an iterator over all subslices of s separated by sep.
-// The iterator yields the same subslices that would be returned by [Split](s, sep),
-// but without constructing a new slice containing the subslices.
-// It returns a single-use iterator.
-func SplitSeq(s, sep []byte) iter.Seq[[]byte] {
-	return splitSeq(s, sep, 0)
-}
-
-// SplitAfterSeq returns an iterator over subslices of s split after each instance of sep.
-// The iterator yields the same subslices that would be returned by [SplitAfter](s, sep),
-// but without constructing a new slice containing the subslices.
-// It returns a single-use iterator.
-func SplitAfterSeq(s, sep []byte) iter.Seq[[]byte] {
-	return splitSeq(s, sep, len(sep))
-}
-
-// FieldsSeq returns an iterator over subslices of s split around runs of
-// whitespace characters, as defined by [unicode.IsSpace].
-// The iterator yields the same subslices that would be returned by [Fields](s),
-// but without constructing a new slice containing the subslices.
-func FieldsSeq(s []byte) iter.Seq[[]byte] {
-	return func(yield func([]byte) bool) {
-		start := -1
-		for i := 0; i < len(s); {
-			size := 1
-			r := rune(s[i])
-			isSpace := asciiSpace[s[i]] != 0
-			if r >= utf8.RuneSelf {
-				r, size = utf8.DecodeRune(s[i:])
-				isSpace = unicode.IsSpace(r)
-			}
-			if isSpace {
-				if start >= 0 {
-					if !yield(s[start:i:i]) {
-						return
-					}
-					start = -1
-				}
-			} else if start < 0 {
-				start = i
-			}
-			i += size
-		}
-		if start >= 0 {
-			yield(s[start:len(s):len(s)])
-		}
-	}
-}
-
-// FieldsFuncSeq returns an iterator over subslices of s split around runs of
-// Unicode code points satisfying f(c).
-// The iterator yields the same subslices that would be returned by [FieldsFunc](s),
-// but without constructing a new slice containing the subslices.
-func FieldsFuncSeq(s []byte, f func(rune) bool) iter.Seq[[]byte] {
-	return func(yield func([]byte) bool) {
-		start := -1
-		for i := 0; i < len(s); {
-			size := 1
-			r := rune(s[i])
-			if r >= utf8.RuneSelf {
-				r, size = utf8.DecodeRune(s[i:])
-			}
-			if f(r) {
-				if start >= 0 {
-					if !yield(s[start:i:i]) {
-						return
-					}
-					start = -1
-				}
-			} else if start < 0 {
-				start = i
-			}
-			i += size
-		}
-		if start >= 0 {
-			yield(s[start:len(s):len(s)])
-		}
-	}
-}

src/bytes/iter_test.go

@@ -1,56 +0,0 @@
-// Copyright 2024 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 bytes_test
-
-import (
-	. "bytes"
-	"testing"
-)
-
-func BenchmarkSplitSeqEmptySeparator(b *testing.B) {
-	for range b.N {
-		for range SplitSeq(benchInputHard, nil) {
-		}
-	}
-}
-
-func BenchmarkSplitSeqSingleByteSeparator(b *testing.B) {
-	sep := []byte("/")
-	for range b.N {
-		for range SplitSeq(benchInputHard, sep) {
-		}
-	}
-}
-
-func BenchmarkSplitSeqMultiByteSeparator(b *testing.B) {
-	sep := []byte("hello")
-	for range b.N {
-		for range SplitSeq(benchInputHard, sep) {
-		}
-	}
-}
-
-func BenchmarkSplitAfterSeqEmptySeparator(b *testing.B) {
-	for range b.N {
-		for range SplitAfterSeq(benchInputHard, nil) {
-		}
-	}
-}
-
-func BenchmarkSplitAfterSeqSingleByteSeparator(b *testing.B) {
-	sep := []byte("/")
-	for range b.N {
-		for range SplitAfterSeq(benchInputHard, sep) {
-		}
-	}
-}
-
-func BenchmarkSplitAfterSeqMultiByteSeparator(b *testing.B) {
-	sep := []byte("hello")
-	for range b.N {
-		for range SplitAfterSeq(benchInputHard, sep) {
-		}
-	}
-}

src/clean.bat

@@ -6,16 +6,27 @@
 
 setlocal
 
-go tool dist env -w -p >env.bat || exit /b 1
+set GOBUILDFAIL=0
+
+go tool dist env -w -p >env.bat
+if errorlevel 1 goto fail
 call .\env.bat
 del env.bat
 echo.
 
-if not exist %GOTOOLDIR%\dist.exe (
-    echo cannot find %GOTOOLDIR%\dist.exe; nothing to clean
-    exit /b 1
-)
+if exist %GOTOOLDIR%\dist.exe goto distok
+echo cannot find %GOTOOLDIR%\dist; nothing to clean
+goto fail
+:distok
 
 "%GOBIN%\go" clean -i std
 "%GOBIN%\go" tool dist clean
 "%GOBIN%\go" clean -i cmd
+
+goto end
+
+:fail
+set GOBUILDFAIL=1
+
+:end
+if x%GOBUILDEXIT%==x1 exit %GOBUILDFAIL%

src/cmd/addr2line/addr2line_test.go

@@ -12,6 +12,7 @@ import (
 	"path/filepath"
 	"runtime"
 	"strings"
+	"sync"
 	"testing"
 )
 
@@ -27,6 +28,26 @@ func TestMain(m *testing.M) {
 	os.Exit(m.Run())
 }
 
+// addr2linePath returns the path to the "addr2line" binary to run.
+func addr2linePath(t testing.TB) string {
+	t.Helper()
+	testenv.MustHaveExec(t)
+
+	addr2linePathOnce.Do(func() {
+		addr2lineExePath, addr2linePathErr = os.Executable()
+	})
+	if addr2linePathErr != nil {
+		t.Fatal(addr2linePathErr)
+	}
+	return addr2lineExePath
+}
+
+var (
+	addr2linePathOnce sync.Once
+	addr2lineExePath  string
+	addr2linePathErr  error
+)
+
 func loadSyms(t *testing.T, dbgExePath string) map[string]string {
 	cmd := testenv.Command(t, testenv.GoToolPath(t), "tool", "nm", dbgExePath)
 	out, err := cmd.CombinedOutput()
@@ -49,7 +70,7 @@ func loadSyms(t *testing.T, dbgExePath string) map[string]string {
 }
 
 func runAddr2Line(t *testing.T, dbgExePath, addr string) (funcname, path, lineno string) {
-	cmd := testenv.Command(t, testenv.Executable(t), dbgExePath)
+	cmd := testenv.Command(t, addr2linePath(t), dbgExePath)
 	cmd.Stdin = strings.NewReader(addr)
 	out, err := cmd.CombinedOutput()
 	if err != nil {
@@ -87,22 +108,27 @@ func testAddr2Line(t *testing.T, dbgExePath, addr string) {
 	// Debug paths are stored slash-separated, so convert to system-native.
 	srcPath = filepath.FromSlash(srcPath)
 	fi2, err := os.Stat(srcPath)
+
 	if err != nil {
 		t.Fatalf("Stat failed: %v", err)
 	}
 	if !os.SameFile(fi1, fi2) {
 		t.Fatalf("addr2line_test.go and %s are not same file", srcPath)
 	}
-	if want := "102"; srcLineNo != want {
+	if want := "124"; srcLineNo != want {
 		t.Fatalf("line number = %v; want %s", srcLineNo, want)
 	}
 }
 
-// This is line 101. The test depends on that.
+// This is line 123. The test depends on that.
 func TestAddr2Line(t *testing.T) {
 	testenv.MustHaveGoBuild(t)
 
-	tmpDir := t.TempDir()
+	tmpDir, err := os.MkdirTemp("", "TestAddr2Line")
+	if err != nil {
+		t.Fatal("TempDir failed: ", err)
+	}
+	defer os.RemoveAll(tmpDir)
 
 	// Build copy of test binary with debug symbols,
 	// since the one running now may not have them.

src/cmd/api/api_test.go

@@ -11,7 +11,7 @@ import (
 	"internal/testenv"
 	"os"
 	"path/filepath"
-	"slices"
+	"sort"
 	"strings"
 	"sync"
 	"testing"
@@ -57,10 +57,7 @@ func TestGolden(t *testing.T) {
 		// TODO(gri) remove extra pkg directory eventually
 		goldenFile := filepath.Join("testdata", "src", "pkg", fi.Name(), "golden.txt")
 		w := NewWalker(nil, "testdata/src/pkg")
-		pkg, err := w.import_(fi.Name())
-		if err != nil {
-			t.Fatalf("import %s: %v", fi.Name(), err)
-		}
+		pkg, _ := w.import_(fi.Name())
 		w.export(pkg)
 
 		if *updateGolden {
@@ -80,7 +77,7 @@ func TestGolden(t *testing.T) {
 			t.Fatalf("opening golden.txt for package %q: %v", fi.Name(), err)
 		}
 		wanted := strings.Split(string(bs), "\n")
-		slices.Sort(wanted)
+		sort.Strings(wanted)
 		for _, feature := range wanted {
 			if feature == "" {
 				continue
@@ -99,11 +96,6 @@ func TestGolden(t *testing.T) {
 }
 
 func TestCompareAPI(t *testing.T) {
-	if *flagCheck {
-		// not worth repeating in -check
-		t.Skip("skipping with -check set")
-	}
-
 	tests := []struct {
 		name                          string
 		features, required, exception []string
@@ -185,11 +177,6 @@ func TestCompareAPI(t *testing.T) {
 }
 
 func TestSkipInternal(t *testing.T) {
-	if *flagCheck {
-		// not worth repeating in -check
-		t.Skip("skipping with -check set")
-	}
-
 	tests := []struct {
 		pkg  string
 		want bool
@@ -214,13 +201,7 @@ func BenchmarkAll(b *testing.B) {
 		for _, context := range contexts {
 			w := NewWalker(context, filepath.Join(testenv.GOROOT(b), "src"))
 			for _, name := range w.stdPackages {
-				pkg, err := w.import_(name)
-				if _, nogo := err.(*build.NoGoError); nogo {
-					continue
-				}
-				if err != nil {
-					b.Fatalf("import %s (%s-%s): %v", name, context.GOOS, context.GOARCH, err)
-				}
+				pkg, _ := w.import_(name)
 				w.export(pkg)
 			}
 			w.Features()
@@ -258,7 +239,8 @@ func TestIssue21181(t *testing.T) {
 		w := NewWalker(context, "testdata/src/issue21181")
 		pkg, err := w.import_("p")
 		if err != nil {
-			t.Fatalf("import %s (%s-%s): %v", "p", context.GOOS, context.GOARCH, err)
+			t.Fatalf("%s: (%s-%s) %s %v", err, context.GOOS, context.GOARCH,
+				pkg.Name(), w.imported)
 		}
 		w.export(pkg)
 	}
@@ -304,20 +286,14 @@ func TestIssue41358(t *testing.T) {
 }
 
 func TestIssue64958(t *testing.T) {
-	if testing.Short() {
-		t.Skip("skipping with -short")
-	}
-	if *flagCheck {
-		// slow, not worth repeating in -check
-		t.Skip("skipping with -check set")
-	}
-	testenv.MustHaveGoBuild(t)
-
 	defer func() {
 		if x := recover(); x != nil {
 			t.Errorf("expected no panic; recovered %v", x)
 		}
 	}()
+
+	testenv.MustHaveGoBuild(t)
+
 	for _, context := range contexts {
 		w := NewWalker(context, "testdata/src/issue64958")
 		pkg, err := w.importFrom("p", "", 0)

src/cmd/api/main_test.go

@@ -25,7 +25,7 @@ import (
 	"path/filepath"
 	"regexp"
 	"runtime"
-	"slices"
+	"sort"
 	"strconv"
 	"strings"
 	"sync"
@@ -232,8 +232,8 @@ func compareAPI(w io.Writer, features, required, exception []string) (ok bool) {
 	featureSet := set(features)
 	exceptionSet := set(exception)
 
-	slices.Sort(features)
-	slices.Sort(required)
+	sort.Strings(features)
+	sort.Strings(required)
 
 	take := func(sl *[]string) string {
 		s := (*sl)[0]
@@ -378,7 +378,7 @@ func (w *Walker) Features() (fs []string) {
 	for f := range w.features {
 		fs = append(fs, f)
 	}
-	slices.Sort(fs)
+	sort.Strings(fs)
 	return
 }
 
@@ -431,7 +431,7 @@ func tagKey(dir string, context *build.Context, tags []string) string {
 	// an indirect imported package. See https://github.com/golang/go/issues/21181
 	// for more detail.
 	tags = append(tags, context.GOOS, context.GOARCH)
-	slices.Sort(tags)
+	sort.Strings(tags)
 
 	for _, tag := range tags {
 		if ctags[tag] {
@@ -535,7 +535,7 @@ func (w *Walker) loadImports() {
 			}
 		}
 
-		slices.Sort(stdPackages)
+		sort.Strings(stdPackages)
 		imports = listImports{
 			stdPackages: stdPackages,
 			importMap:   importMap,
@@ -717,7 +717,7 @@ func sortedMethodNames(typ *types.Interface) []string {
 	for i := range list {
 		list[i] = typ.Method(i).Name()
 	}
-	slices.Sort(list)
+	sort.Strings(list)
 	return list
 }
 
@@ -747,7 +747,7 @@ func (w *Walker) sortedEmbeddeds(typ *types.Interface) []string {
 			list = append(list, buf.String())
 		}
 	}
-	slices.Sort(list)
+	sort.Strings(list)
 	return list
 }
 
@@ -1019,7 +1019,7 @@ func (w *Walker) emitType(obj *types.TypeName) {
 
 func (w *Walker) emitStructType(name string, typ *types.Struct) {
 	typeStruct := fmt.Sprintf("type %s struct", name)
-	w.emitf("%s", typeStruct)
+	w.emitf(typeStruct)
 	defer w.pushScope(typeStruct)()
 
 	for i := 0; i < typ.NumFields(); i++ {
@@ -1058,7 +1058,7 @@ func (w *Walker) emitIfaceType(name string, typ *types.Interface) {
 		if w.isDeprecated(m) {
 			w.emitf("%s //deprecated", m.Name())
 		}
-		w.emitf("%s%s", m.Name(), w.signatureString(m.Signature()))
+		w.emitf("%s%s", m.Name(), w.signatureString(m.Type().(*types.Signature)))
 	}
 
 	if !complete {
@@ -1083,12 +1083,12 @@ func (w *Walker) emitIfaceType(name string, typ *types.Interface) {
 		return
 	}
 
-	slices.Sort(methodNames)
+	sort.Strings(methodNames)
 	w.emitf("type %s interface { %s }", name, strings.Join(methodNames, ", "))
 }
 
 func (w *Walker) emitFunc(f *types.Func) {
-	sig := f.Signature()
+	sig := f.Type().(*types.Signature)
 	if sig.Recv() != nil {
 		panic("method considered a regular function: " + f.String())
 	}

src/cmd/asm/internal/arch/arch.go

@@ -520,27 +520,15 @@ func archLoong64(linkArch *obj.LinkArch) *Arch {
 	for i := loong64.REG_R0; i <= loong64.REG_R31; i++ {
 		register[obj.Rconv(i)] = int16(i)
 	}
-
 	for i := loong64.REG_F0; i <= loong64.REG_F31; i++ {
 		register[obj.Rconv(i)] = int16(i)
 	}
-
 	for i := loong64.REG_FCSR0; i <= loong64.REG_FCSR31; i++ {
 		register[obj.Rconv(i)] = int16(i)
 	}
-
 	for i := loong64.REG_FCC0; i <= loong64.REG_FCC31; i++ {
 		register[obj.Rconv(i)] = int16(i)
 	}
-
-	for i := loong64.REG_V0; i <= loong64.REG_V31; i++ {
-		register[obj.Rconv(i)] = int16(i)
-	}
-
-	for i := loong64.REG_X0; i <= loong64.REG_X31; i++ {
-		register[obj.Rconv(i)] = int16(i)
-	}
-
 	// Pseudo-registers.
 	register["SB"] = RSB
 	register["FP"] = RFP
@@ -553,8 +541,6 @@ func archLoong64(linkArch *obj.LinkArch) *Arch {
 		"FCSR": true,
 		"FCC":  true,
 		"R":    true,
-		"V":    true,
-		"X":    true,
 	}
 
 	instructions := make(map[string]obj.As)
@@ -600,10 +586,6 @@ func archRISCV64(shared bool) *Arch {
 		name := fmt.Sprintf("F%d", i-riscv.REG_F0)
 		register[name] = int16(i)
 	}
-	for i := riscv.REG_V0; i <= riscv.REG_V31; i++ {
-		name := fmt.Sprintf("V%d", i-riscv.REG_V0)
-		register[name] = int16(i)
-	}
 
 	// General registers with ABI names.
 	register["ZERO"] = riscv.REG_ZERO

src/cmd/asm/internal/arch/arm.go

@@ -101,7 +101,7 @@ func IsARMCMP(op obj.As) bool {
 // one of the STREX-like instructions that require special handling.
 func IsARMSTREX(op obj.As) bool {
 	switch op {
-	case arm.ASTREX, arm.ASTREXD, arm.ASTREXB, arm.ASWPW, arm.ASWPBU:
+	case arm.ASTREX, arm.ASTREXD, arm.ASWPW, arm.ASWPBU:
 		return true
 	}
 	return false

src/cmd/asm/internal/arch/arm64.go

@@ -59,10 +59,10 @@ func jumpArm64(word string) bool {
 
 var arm64SpecialOperand map[string]arm64.SpecialOperand
 
-// ARM64SpecialOperand returns the internal representation of a special operand.
-func ARM64SpecialOperand(name string) arm64.SpecialOperand {
+// GetARM64SpecialOperand returns the internal representation of a special operand.
+func GetARM64SpecialOperand(name string) arm64.SpecialOperand {
 	if arm64SpecialOperand == nil {
-		// Generate mapping when function is first called.
+		// Generate the mapping automatically when the first time the function is called.
 		arm64SpecialOperand = map[string]arm64.SpecialOperand{}
 		for opd := arm64.SPOP_BEGIN; opd < arm64.SPOP_END; opd++ {
 			arm64SpecialOperand[opd.String()] = opd

src/cmd/asm/internal/arch/loong64.go

@@ -11,8 +11,6 @@ package arch
 import (
 	"cmd/internal/obj"
 	"cmd/internal/obj/loong64"
-	"errors"
-	"fmt"
 )
 
 func jumpLoong64(word string) bool {
@@ -23,6 +21,17 @@ func jumpLoong64(word string) bool {
 	return false
 }
 
+// IsLoong64CMP reports whether the op (as defined by an loong64.A* constant) is
+// one of the CMP instructions that require special handling.
+func IsLoong64CMP(op obj.As) bool {
+	switch op {
+	case loong64.ACMPEQF, loong64.ACMPEQD, loong64.ACMPGEF, loong64.ACMPGED,
+		loong64.ACMPGTF, loong64.ACMPGTD:
+		return true
+	}
+	return false
+}
+
 // IsLoong64MUL reports whether the op (as defined by an loong64.A* constant) is
 // one of the MUL/DIV/REM instructions that require special handling.
 func IsLoong64MUL(op obj.As) bool {
@@ -50,82 +59,6 @@ func IsLoong64AMO(op obj.As) bool {
 	return loong64.IsAtomicInst(op)
 }
 
-var loong64ElemExtMap = map[string]int16{
-	"B":  loong64.ARNG_B,
-	"H":  loong64.ARNG_H,
-	"W":  loong64.ARNG_W,
-	"V":  loong64.ARNG_V,
-	"BU": loong64.ARNG_BU,
-	"HU": loong64.ARNG_HU,
-	"WU": loong64.ARNG_WU,
-	"VU": loong64.ARNG_VU,
-}
-
-var loong64LsxArngExtMap = map[string]int16{
-	"B16": loong64.ARNG_16B,
-	"H8":  loong64.ARNG_8H,
-	"W4":  loong64.ARNG_4W,
-	"V2":  loong64.ARNG_2V,
-}
-
-var loong64LasxArngExtMap = map[string]int16{
-	"B32": loong64.ARNG_32B,
-	"H16": loong64.ARNG_16H,
-	"W8":  loong64.ARNG_8W,
-	"V4":  loong64.ARNG_4V,
-	"Q2":  loong64.ARNG_2Q,
-}
-
-// Loong64RegisterExtension constructs an Loong64 register with extension or arrangement.
-func Loong64RegisterExtension(a *obj.Addr, ext string, reg, num int16, isAmount, isIndex bool) error {
-	var ok bool
-	var arng_type int16
-	var simd_type int16
-
-	switch {
-	case reg >= loong64.REG_V0 && reg <= loong64.REG_V31:
-		simd_type = loong64.LSX
-	case reg >= loong64.REG_X0 && reg <= loong64.REG_X31:
-		simd_type = loong64.LASX
-	default:
-		return errors.New("Loong64 extension: invalid LSX/LASX register: " + fmt.Sprintf("%d", reg))
-	}
-
-	if isIndex {
-		arng_type, ok = loong64ElemExtMap[ext]
-		if !ok {
-			return errors.New("Loong64 extension: invalid LSX/LASX arrangement type: " + ext)
-		}
-
-		a.Reg = loong64.REG_ELEM
-		a.Reg += ((reg & loong64.EXT_REG_MASK) << loong64.EXT_REG_SHIFT)
-		a.Reg += ((arng_type & loong64.EXT_TYPE_MASK) << loong64.EXT_TYPE_SHIFT)
-		a.Reg += ((simd_type & loong64.EXT_SIMDTYPE_MASK) << loong64.EXT_SIMDTYPE_SHIFT)
-		a.Index = num
-	} else {
-		switch simd_type {
-		case loong64.LSX:
-			arng_type, ok = loong64LsxArngExtMap[ext]
-			if !ok {
-				return errors.New("Loong64 extension: invalid LSX arrangement type: " + ext)
-			}
-
-		case loong64.LASX:
-			arng_type, ok = loong64LasxArngExtMap[ext]
-			if !ok {
-				return errors.New("Loong64 extension: invalid LASX arrangement type: " + ext)
-			}
-		}
-
-		a.Reg = loong64.REG_ARNG
-		a.Reg += ((reg & loong64.EXT_REG_MASK) << loong64.EXT_REG_SHIFT)
-		a.Reg += ((arng_type & loong64.EXT_TYPE_MASK) << loong64.EXT_TYPE_SHIFT)
-		a.Reg += ((simd_type & loong64.EXT_SIMDTYPE_MASK) << loong64.EXT_SIMDTYPE_SHIFT)
-	}
-
-	return nil
-}
-
 func loong64RegisterNumber(name string, n int16) (int16, bool) {
 	switch name {
 	case "F":
@@ -144,14 +77,6 @@ func loong64RegisterNumber(name string, n int16) (int16, bool) {
 		if 0 <= n && n <= 31 {
 			return loong64.REG_R0 + n, true
 		}
-	case "V":
-		if 0 <= n && n <= 31 {
-			return loong64.REG_V0 + n, true
-		}
-	case "X":
-		if 0 <= n && n <= 31 {
-			return loong64.REG_X0 + n, true
-		}
 	}
 	return 0, false
 }

src/cmd/asm/internal/arch/ppc64.go

@@ -25,7 +25,7 @@ func jumpPPC64(word string) bool {
 // one of the CMP instructions that require special handling.
 func IsPPC64CMP(op obj.As) bool {
 	switch op {
-	case ppc64.ACMP, ppc64.ACMPU, ppc64.ACMPW, ppc64.ACMPWU, ppc64.AFCMPO, ppc64.AFCMPU, ppc64.ADCMPO, ppc64.ADCMPU, ppc64.ADCMPOQ, ppc64.ADCMPUQ:
+	case ppc64.ACMP, ppc64.ACMPU, ppc64.ACMPW, ppc64.ACMPWU, ppc64.AFCMPO, ppc64.AFCMPU:
 		return true
 	}
 	return false

src/cmd/asm/internal/arch/riscv64.go

@@ -13,8 +13,9 @@ import (
 	"cmd/internal/obj/riscv"
 )
 
-// IsRISCV64AMO reports whether op is an AMO instruction that requires
-// special handling.
+// IsRISCV64AMO reports whether the op (as defined by a riscv.A*
+// constant) is one of the AMO instructions that requires special
+// handling.
 func IsRISCV64AMO(op obj.As) bool {
 	switch op {
 	case riscv.ASCW, riscv.ASCD, riscv.AAMOSWAPW, riscv.AAMOSWAPD, riscv.AAMOADDW, riscv.AAMOADDD,
@@ -25,33 +26,3 @@ func IsRISCV64AMO(op obj.As) bool {
 	}
 	return false
 }
-
-// IsRISCV64VTypeI reports whether op is a vtype immediate instruction that
-// requires special handling.
-func IsRISCV64VTypeI(op obj.As) bool {
-	return op == riscv.AVSETVLI || op == riscv.AVSETIVLI
-}
-
-var riscv64SpecialOperand map[string]riscv.SpecialOperand
-
-// RISCV64SpecialOperand returns the internal representation of a special operand.
-func RISCV64SpecialOperand(name string) riscv.SpecialOperand {
-	if riscv64SpecialOperand == nil {
-		// Generate mapping when function is first called.
-		riscv64SpecialOperand = map[string]riscv.SpecialOperand{}
-		for opd := riscv.SPOP_BEGIN; opd < riscv.SPOP_END; opd++ {
-			riscv64SpecialOperand[opd.String()] = opd
-		}
-	}
-	if opd, ok := riscv64SpecialOperand[name]; ok {
-		return opd
-	}
-	return riscv.SPOP_END
-}
-
-// RISCV64ValidateVectorType reports whether the given configuration is a
-// valid vector type.
-func RISCV64ValidateVectorType(vsew, vlmul, vtail, vmask int64) error {
-	_, err := riscv.EncodeVectorType(vsew, vlmul, vtail, vmask)
-	return err
-}