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diff --git a/doc/go1.19.html b/doc/go1.19.html deleted file mode 100644 index de1dfefd4d..0000000000 --- a/doc/go1.19.html +++ /dev/null @@ -1,985 +0,0 @@ -<!--{ - "Title": "Go 1.19 Release Notes", - "Path": "/doc/go1.19" -}--> -<!-- -NOTE: In this document and others in this directory, the convention is to -set fixed-width phrases with non-fixed-width spaces, as in -<code>hello</code> <code>world</code>. -Do not send CLs removing the interior tags from such phrases. ---> -<style> - main ul li { margin: 0.5em 0; } -</style> -<h2 id="introduction">DRAFT RELEASE NOTES — Introduction to Go 1.19</h2> -<p> - <strong> - Go 1.19 is not yet released. These are work-in-progress - release notes. Go 1.19 is expected to be released in August 2022. - </strong> -</p> - -<h2 id="language">Changes to the language</h2> - -<p><!-- https://go.dev/issue/52038 --> - There is only one small change to the language, - a <a href="https://github.com/golang/go/issues/52038">very small correction</a> - to the <a href="/ref/spec#Declarations_and_scope">scope of type parameters in method declarations</a>. - Existing programs are unaffected. -</p> - -<h2 id="mem">Memory Model</h2> - -<p><!-- https://go.dev/issue/50859 --> - The <a href="/ref/mem">Go memory model</a> has been revised to align Go with - the memory model used by C, C++, Java, JavaScript, Rust, and Swift. - Go only provides sequentially consistent atomics, not any of the more relaxed forms found in other languages. - Along with the memory model update, - Go 1.19 introduces <a href="#atomic_types">new types in the <code>sync/atomic</code> package</a> - that make it easier to use atomic values, such as - <a href="/pkg/sync/atomic/#Int64">atomic.Int64</a> - and - <a href="/pkg/sync/atomic/#Pointer">atomic.Pointer[T]</a>. -</p> - -<h2 id="ports">Ports</h2> - -<h3 id="loong64">Loongson 64-bit</h3> -<p><!-- https://go.dev/issue/46229 --> - Go 1.19 adds support for the Loongson 64-bit architecture LoongArch - on Linux (<code>GOOS=linux</code>, <code>GOARCH=loong64</code>). -</p> - -<h3 id="riscv64">RISC-V</h3> -<p><!-- CL 402374 --> - The <code>riscv64</code> port now supports passing function arguments - and result using registers. Benchmarking shows typical performance - improvements of 10% or more on <code>riscv64</code>. -</p> - -<h2 id="tools">Tools</h2> - -<h3 id="go-doc">Doc Comments</h3> - -<p><!-- https://go.dev/issue/51082 --><!-- CL 384265, CL 397276, CL 397278, CL 397279, CL 397281, CL 397284 --> -Go 1.19 adds support for links, lists, and clearer headings in doc comments. -As part of this change, <a href="/cmd/gofmt"><code>gofmt</code></a> -now reformats doc comments to make their rendered meaning clearer. -See “<a href="/doc/comment">Go Doc Comments</a>” -for syntax details and descriptions of common mistakes now highlighted by <code>gofmt</code>. -As another part of this change, the new package <a href="/pkg/go/doc/comment">go/doc/comment</a> -provides parsing and reformatting of doc comments -as well as support for rendering them to HTML, Markdown, and text. -</p> - -<h3 id="go-unix">New <code>unix</code> build constraint</h3> - -<p><!-- CL 389934 --><!-- https://go.dev/issue/20322 --><!-- https://go.dev/issue/51572 --> - The build constraint <code>unix</code> is now recognized - in <code>//go:build</code> lines. The constraint is satisfied - if the target operating system, also known as <code>GOOS</code>, is - a Unix or Unix-like system. For the 1.19 release it is satisfied - if <code>GOOS</code> is one of - <code>aix</code>, <code>android</code>, <code>darwin</code>, - <code>dragonfly</code>, <code>freebsd</code>, <code>hurd</code>, - <code>illumos</code>, <code>ios</code>, <code>linux</code>, - <code>netbsd</code>, <code>openbsd</code>, or <code>solaris</code>. - In future releases the <code>unix</code> constraint may match - additional newly supported operating systems. -</p> - -<h3 id="go-command">Go command</h3> - -<!-- https://go.dev/issue/51461 --> -<p> - The <code>-trimpath</code> flag, if set, is now included in the build settings - stamped into Go binaries by <code>go</code> <code>build</code>, and can be - examined using - <a href="https://pkg.go.dev/cmd/go#hdr-Print_Go_version"><code>go</code> <code>version</code> <code>-m</code></a> - or <a href="https://pkg.go.dev/runtime/debug#ReadBuildInfo"><code>debug.ReadBuildInfo</code></a>. -</p> -<p> - <code>go</code> <code>generate</code> now sets the <code>GOROOT</code> - environment variable explicitly in the generator's environment, so that - generators can locate the correct <code>GOROOT</code> even if built - with <code>-trimpath</code>. -</p> - -<p><!-- CL 404134 --> - <code>go</code> <code>test</code> and <code>go</code> <code>generate</code> now place - <code>GOROOT/bin</code> at the beginning of the <code>PATH</code> used for the - subprocess, so tests and generators that execute the <code>go</code> command - will resolve it to same <code>GOROOT</code>. -</p> - -<p><!-- CL 398058 --> - <code>go</code> <code>env</code> now quotes entries that contain spaces in - the <code>CGO_CFLAGS</code>, <code>CGO_CPPFLAGS</code>, <code>CGO_CXXFLAGS</code>, <code>CGO_FFLAGS</code>, <code>CGO_LDFLAGS</code>, - and <code>GOGCCFLAGS</code> variables it reports. -</p> - -<p><!-- https://go.dev/issue/29666 --> - <code>go</code> <code>list</code> <code>-json</code> now accepts a - comma-separated list of JSON fields to populate. If a list is specified, - the JSON output will include only those fields, and - <code>go</code> <code>list</code> may avoid work to compute fields that are - not included. In some cases, this may suppress errors that would otherwise - be reported. -</p> - -<p><!-- CL 410821 --> - The <code>go</code> command now caches information necessary to load some modules, - which should result in a speed-up of some <code>go</code> <code>list</code> invocations. -</p> - -<h3 id="vet">Vet</h3> - -<p><!-- https://go.dev/issue/47528 --> - The <code>vet</code> checker “errorsas” now reports when - <a href="/pkg/errors/#As"><code>errors.As</code></a> is called - with a second argument of type <code>*error</code>, - a common mistake. -</p> - -<h2 id="runtime">Runtime</h2> - -<p><!-- https://go.dev/issue/48409 --><!-- CL 397018 --> - The runtime now includes support for a soft memory limit. This memory limit - includes the Go heap and all other memory managed by the runtime, and - excludes external memory sources such as mappings of the binary itself, - memory managed in other languages, and memory held by the operating system on - behalf of the Go program. This limit may be managed via - <a href="/pkg/runtime/debug/#SetMemoryLimit"><code>runtime/debug.SetMemoryLimit</code></a> - or the equivalent - <a href="/pkg/runtime/#hdr-Environment_Variables"><code>GOMEMLIMIT</code></a> - environment variable. The limit works in conjunction with - <a href="/pkg/runtime/debug/#SetGCPercent"><code>runtime/debug.SetGCPercent</code></a> - / <a href="/pkg/runtime/#hdr-Environment_Variables"><code>GOGC</code></a>, - and will be respected even if <code>GOGC=off</code>, allowing Go programs to - always make maximal use of their memory limit, improving resource efficiency - in some cases. See <a href="/doc/gc-guide">the GC guide</a> for - a detailed guide explaining the soft memory limit in more detail, as well as - a variety of common use-cases and scenarios. Please note that small memory - limits, on the order of tens of megabytes or less, are less likely to be - respected due to external latency factors, such as OS scheduling. See - <a href="https://go.dev/issue/52433">issue 52433</a> for more details. Larger - memory limits, on the order of hundreds of megabytes or more, are stable and - production-ready. -</p> - -<p><!-- CL 353989 --> - In order to limit the effects of GC thrashing when the program's live heap - size approaches the soft memory limit, the Go runtime also attempts to limit - total GC CPU utilization to 50%, excluding idle time, choosing to use more - memory over preventing application progress. In practice, we expect this limit - to only play a role in exceptional cases, and the new - <a href="/pkg/runtime/metrics/#hdr-Supported_metrics">runtime metric</a> - <code>/gc/limiter/last-enabled:gc-cycle</code> reports when this last - occurred. -</p> - -<p><!-- https://go.dev/issue/44163 --> - The runtime now schedules many fewer GC worker goroutines on idle operating - system threads when the application is idle enough to force a periodic GC - cycle. -</p> - -<p><!-- https://go.dev/issue/18138 --><!-- CL 345889 --> - The runtime will now allocate initial goroutine stacks based on the historic - average stack usage of goroutines. This avoids some of the early stack growth - and copying needed in the average case in exchange for at most 2x wasted - space on below-average goroutines. -</p> - -<p><!-- https://go.dev/issue/46279 --><!-- CL 393354 --><!-- CL 392415 --> - On Unix operating systems, Go programs that import package - <a href="/pkg/os/">os</a> now automatically increase the open file limit - (<code>RLIMIT_NOFILE</code>) to the maximum allowed value; - that is, they change the soft limit to match the hard limit. - This corrects artificially low limits set on some systems for compatibility with very old C programs using the - <a href="https://en.wikipedia.org/wiki/Select_(Unix)"><i>select</i></a> system call. - Go programs are not helped by that limit, and instead even simple programs like <code>gofmt</code> - often ran out of file descriptors on such systems when processing many files in parallel. - One impact of this change is that Go programs that in turn execute very old C programs in child processes - may run those programs with too high a limit. - This can be corrected by setting the hard limit before invoking the Go program. -</p> - -<p><!-- https://go.dev/issue/51485 --><!-- CL 390421 --> - Unrecoverable fatal errors (such as concurrent map writes, or unlock of - unlocked mutexes) now print a simpler traceback excluding runtime metadata - (equivalent to a fatal panic) unless <code>GOTRACEBACK=system</code> or - <code>crash</code>. Runtime-internal fatal error tracebacks always include - full metadata regardless of the value of <code>GOTRACEBACK</code> -</p> - -<p><!-- https://go.dev/issue/50614 --><!-- CL 395754 --> - Support for debugger-injected function calls has been added on ARM64, - enabling users to call functions from their binary in an interactive - debugging session when using a debugger that is updated to make use of this - functionality. -</p> - -<p><!-- https://go.dev/issue/44853 --> - The <a href="/doc/go1.18#go-build-asan">address sanitizer support added in Go 1.18</a> - now handles function arguments and global variables more precisely. -</p> - -<h2 id="compiler">Compiler</h2> - -<p><!-- https://go.dev/issue/5496 --><!-- CL 357330, 395714, 403979 --> - The compiler now uses - a <a href="https://en.wikipedia.org/wiki/Branch_table">jump - table</a> to implement large integer and string switch statements. - Performance improvements for the switch statement vary but can be - on the order of 20% faster. - (<code>GOARCH=amd64</code> and <code>GOARCH=arm64</code> only) -</p> -<p><!-- CL 391014 --> - The Go compiler now requires the <code>-p=importpath</code> flag to - build a linkable object file. This is already supplied by - the <code>go</code> command and by Bazel. Any other build systems - that invoke the Go compiler directly will need to make sure they - pass this flag as well. -</p> - -<h2 id="assembler">Assembler</h2> -<p><!-- CL 404298 --> - Like the compiler, the assembler now requires the - <code>-p=importpath</code> flag to build a linkable object file. - This is already supplied by the <code>go</code> command. Any other - build systems that invoke the Go assembler directly will need to - make sure they pass this flag as well. -</p> - -<h2 id="linker">Linker</h2> -<p><!-- https://go.dev/issue/50796, CL 380755 --> - On ELF platforms, the linker now emits compressed DWARF sections in - the standard gABI format (<code>SHF_COMPRESSED</code>), instead of - the legacy <code>.zdebug</code> format. -</p> - -<h2 id="library">Core library</h2> - -<h3 id="atomic_types">New atomic types</h3> - -<p><!-- https://go.dev/issue/50860 --><!-- CL 381317 --> - The <a href="/pkg/sync/atomic/"><code>sync/atomic</code></a> package defines new atomic types - <a href="/pkg/sync/atomic/#Bool"><code>Bool</code></a>, - <a href="/pkg/sync/atomic/#Int32"><code>Int32</code></a>, - <a href="/pkg/sync/atomic/#Int64"><code>Int64</code></a>, - <a href="/pkg/sync/atomic/#Uint32"><code>Uint32</code></a>, - <a href="/pkg/sync/atomic/#Uint64"><code>Uint64</code></a>, - <a href="/pkg/sync/atomic/#Uintptr"><code>Uintptr</code></a>, and - <a href="/pkg/sync/atomic/#Pointer"><code>Pointer</code></a>. - These types hide the underlying values so that all accesses are forced to use - the atomic APIs. - <a href="/pkg/sync/atomic/#Pointer"><code>Pointer</code></a> also avoids - the need to convert to - <a href="/pkg/unsafe/#Pointer"><code>unsafe.Pointer</code></a> at call sites. - <a href="/pkg/sync/atomic/#Int64"><code>Int64</code></a> and - <a href="/pkg/sync/atomic/#Uint64"><code>Uint64</code></a> are - automatically aligned to 64-bit boundaries in structs and allocated data, - even on 32-bit systems. -</p> - -<h3 id="os-exec-path">PATH lookups</h3> - -<p><!-- https://go.dev/issue/43724 --> - <!-- CL 381374 --><!-- CL 403274 --> - <a href="/pkg/os/exec/#Command"><code>Command</code></a> and - <a href="/pkg/os/exec/#LookPath"><code>LookPath</code></a> no longer - allow results from a PATH search to be found relative to the current directory. - This removes a <a href="/blog/path-security">common source of security problems</a> - but may also break existing programs that depend on using, say, <code>exec.Command("prog")</code> - to run a binary named <code>prog</code> (or, on Windows, <code>prog.exe</code>) in the current directory. - See the <a href="/pkg/os/exec/"><code>os/exec</code></a> package documentation for - information about how best to update such programs. -</p> - -<p><!-- https://go.dev/issue/43947 --> - On Windows, <code>Command</code> and <code>LookPath</code> now respect the - <a href="https://docs.microsoft.com/en-us/windows/win32/api/processenv/nf-processenv-needcurrentdirectoryforexepatha"><code>NoDefaultCurrentDirectoryInExePath</code></a> - environment variable, making it possible to disable - the default implicit search of “<code>.</code>” in PATH lookups on Windows systems. -</p> - -<h3 id="minor_library_changes">Minor changes to the library</h3> -<p> - As always, there are various minor changes and updates to the library, - made with the Go 1 <a href="/doc/go1compat">promise of compatibility</a> - in mind. - There are also various performance improvements, not enumerated here. -</p> - -<dl id="archive/zip"><dt><a href="/pkg/archive/zip/">archive/zip</a></dt> - <dd> - <p><!-- CL 387976 --> - <a href="/pkg/archive/zip/#Reader"><code>Reader</code></a> - now ignores non-ZIP data at the start of a ZIP file, matching most other implementations. - This is necessary to read some Java JAR files, among other uses. - </p> - </dd> -</dl><!-- archive/zip --> - -<dl id="crypto/elliptic"><dt><a href="/pkg/crypto/elliptic/">crypto/elliptic</a></dt> - <dd> - <p><!-- CL 382995 --> - Operating on invalid curve points (those for which the - <code>IsOnCurve</code> method returns false, and which are never returned - by <code>Unmarshal</code> or by a <code>Curve</code> method operating on a - valid point) has always been undefined behavior and can lead to key - recovery attacks. If an invalid point is supplied to - <a href="/pkg/crypto/elliptic/#Marshal"><code>Marshal</code></a>, - <a href="/pkg/crypto/elliptic/#MarshalCompressed"><code>MarshalCompressed</code></a>, - <a href="/pkg/crypto/elliptic/#Curve.Add"><code>Add</code></a>, - <a href="/pkg/crypto/elliptic/#Curve.Double"><code>Double</code></a>, or - <a href="/pkg/crypto/elliptic/#Curve.ScalarMult"><code>ScalarMult</code></a>, - they will now panic. - </p> - - <p><!-- golang.org/issue/52182 --> - <code>ScalarBaseMult</code> operations on the <code>P224</code>, - <code>P384</code>, and <code>P521</code> curves are now up to three - times faster, leading to similar speedups in some ECDSA operations. The - generic (not platform optimized) <code>P256</code> implementation was - replaced with one derived from a formally verified model; this might - lead to significant slowdowns on 32-bit platforms. - </p> - </dd> -</dl><!-- crypto/elliptic --> - -<dl id="crypto/rand"><dt><a href="/pkg/crypto/rand/">crypto/rand</a></dt> - <dd> - <p><!-- CL 370894 --><!-- CL 390038 --> - <a href="/pkg/crypto/rand/#Read"><code>Read</code></a> no longer buffers - random data obtained from the operating system between calls. Applications - that perform many small reads at high frequency might choose to wrap - <a href="/pkg/crypto/rand/#Reader"><code>Reader</code></a> in a - <a href="/pkg/bufio/#Reader"><code>bufio.Reader</code></a> for performance - reasons, taking care to use - <a href="/pkg/io/#ReadFull"><code>io.ReadFull</code></a> - to ensure no partial reads occur. - </p> - - <p><!-- CL 375215 --> - On Plan 9, <code>Read</code> has been reimplemented, replacing the ANSI - X9.31 algorithm with a fast key erasure generator. - </p> - - <p><!-- CL 391554 --><!-- CL 387554 --> - The <a href="/pkg/crypto/rand/#Prime"><code>Prime</code></a> - implementation was simplified. This will lead to different outputs for the - same random stream compared to the previous implementation. The internals - of <code>Prime</code> are not stable, should not be relied upon not to - change, and the output is now intentionally non-deterministic with respect - to the input stream. - </p> - </dd> -</dl><!-- crypto/rand --> - -<dl id="crypto/tls"><dt><a href="/pkg/crypto/tls/">crypto/tls</a></dt> - <dd> - <p><!-- CL 400974 --><!-- https://go.dev/issue/45428 --> - The <code>tls10default</code> <code>GODEBUG</code> option has been - removed. It is still possible to enable TLS 1.0 client-side by setting - <a href="/pkg/crypto/tls#Config.MinVersion"><code>Config.MinVersion</code></a>. - </p> - - <p><!-- CL 384894 --> - The TLS server and client now reject duplicate extensions in TLS - handshakes, as required by RFC 5246, Section 7.4.1.4 and RFC 8446, Section - 4.2. - </p> - </dd> -</dl><!-- crypto/tls --> - -<dl id="crypto/x509"><dt><a href="/pkg/crypto/x509/">crypto/x509</a></dt> - <dd> - <p><!-- CL 285872 --> - <a href="/pkg/crypto/x509/#CreateCertificate"><code>CreateCertificate</code></a> - no longer supports creating certificates with <code>SignatureAlgorithm</code> - set to <code>MD5WithRSA</code>. - </p> - - <p><!-- CL 400494 --> - <code>CreateCertificate</code> no longer accepts negative serial numbers. - </p> - - <p><!-- CL 399827 --> - <code>CreateCertificate</code> will not emit an empty SEQUENCE anymore - when the produced certificate has no extensions. - </p> - - <p><!-- CL 396774 --> - Removal of the <code>x509sha1=1</code> <code>GODEBUG</code> option, - originally planned for Go 1.19, has been rescheduled to a future release. - Applications using it should work on migrating. Practical attacks against - SHA-1 have been demonstrated since 2017 and publicly trusted Certificate - Authorities have not issued SHA-1 certificates since 2015. - </p> - - <p><!-- CL 383215 --> - <a href="/pkg/crypto/x509/#ParseCertificate"><code>ParseCertificate</code></a> - and <a href="/pkg/crypto/x509/#ParseCertificateRequest"><code>ParseCertificateRequest</code></a> - now reject certificates and CSRs which contain duplicate extensions. - </p> - - <p><!-- https://go.dev/issue/46057 --><!-- https://go.dev/issue/35044 --><!-- CL 398237 --><!-- CL 400175 --><!-- CL 388915 --> - The new <a href="/pkg/crypto/x509/#CertPool.Clone"><code>CertPool.Clone</code></a> - and <a href="/pkg/crypto/x509/#CertPool.Equal"><code>CertPool.Equal</code></a> - methods allow cloning a <code>CertPool</code> and checking the equivalence of two - <code>CertPool</code>s respectively. - </p> - - <p><!-- https://go.dev/issue/50674 --><!-- CL 390834 --> - The new function <a href="/pkg/crypto/x509/#ParseRevocationList"><code>ParseRevocationList</code></a> - provides a faster, safer to use CRL parser which returns a - <a href="/pkg/crypto/x509/#RevocationList"><code>RevocationList</code></a>. - Parsing a CRL also populates the new <code>RevocationList</code> fields - <code>RawIssuer</code>, <code>Signature</code>, - <code>AuthorityKeyId</code>, and <code>Extensions</code>, which are ignored by - <a href="/pkg/crypto/x509/#CreateRevocationList"><code>CreateRevocationList</code></a>. - </p><p> - The new method <a href="/pkg/crypto/x509/#RevocationList.CheckSignatureFrom"><code>RevocationList.CheckSignatureFrom</code></a> - checks that the signature on a CRL is a valid signature from a - <a href="/pkg/crypto/x509/#Certificate"><code>Certificate</code></a>. - </p><p> - The <a href="/pkg/crypto/x509/#ParseCRL"><code>ParseCRL</code></a> and - <a href="/pkg/crypto/x509/#ParseDERCRL"><code>ParseDERCRL</code></a> functions - are now deprecated in favor of <code>ParseRevocationList</code>. - The <a href="/pkg/crypto/x509#Certificate.CheckCRLSignature"><code>Certificate.CheckCRLSignature</code></a> - method is deprecated in favor of <code>RevocationList.CheckSignatureFrom</code>. - </p> - - <p><!-- CL 389555, CL 401115, CL 403554 --> - The path builder of <a href="/pkg/crypto/x509/#Certificate.Verify"><code>Certificate.Verify</code></a> - was overhauled and should now produce better chains and/or be more efficient in complicated scenarios. - Name constraints are now also enforced on non-leaf certificates. - </p> - </dd> -</dl><!-- crypto/x509 --> - -<dl id="crypto/x509/pkix"><dt><a href="/pkg/crypto/x509/pkix">crypto/x509/pkix</a></dt> - <dd> - <p><!-- CL 390834 --> - The types <a href="/pkg/crypto/x509/pkix#CertificateList"><code>CertificateList</code></a> and - <a href="/pkg/crypto/x509/pkix#TBSCertificateList"><code>TBSCertificateList</code></a> - have been deprecated. The new <a href="#crypto/x509"><code>crypto/x509</code> CRL functionality</a> - should be used instead. - </p> - </dd> -</dl><!-- crypto/x509/pkix --> - -<dl id="debug/elf"><dt><a href="/pkg/debug/elf">debug/elf</a></dt> - <dd> - <p><!-- CL 396735 --> - The new <code>EM_LONGARCH</code> and <code>R_LARCH_*</code> constants - support the loong64 port. - </p> - </dd> -</dl><!-- debug/elf --> - -<dl id="debug/pe"><dt><a href="/pkg/debug/pe/">debug/pe</a></dt> - <dd> - <p><!-- https://go.dev/issue/51868 --><!-- CL 394534 --> - The new <a href="/pkg/debug/pe/#File.COFFSymbolReadSectionDefAux"><code>File.COFFSymbolReadSectionDefAux</code></a> - method, which returns a <a href="/pkg/debug/pe/#COFFSymbolAuxFormat5"><code>COFFSymbolAuxFormat5</code></a>, - provides access to COMDAT information in PE file sections. - These are supported by new <code>IMAGE_COMDAT_*</code> and <code>IMAGE_SCN_*</code> constants. - </p> - </dd> -</dl><!-- debug/pe --> - -<dl id="encoding/binary"><dt><a href="/pkg/encoding/binary/">encoding/binary</a></dt> - <dd> - <p><!-- https://go.dev/issue/50601 --><!-- CL 386017 --><!-- CL 389636 --> - The new interface - <a href="/pkg/encoding/binary/#AppendByteOrder"><code>AppendByteOrder</code></a> - provides efficient methods for appending a <code>uint16</code>, <code>uint32</code>, or <code>uint64</code> - to a byte slice. - <a href="/pkg/encoding/binary/#BigEndian"><code>BigEndian</code></a> and - <a href="/pkg/encoding/binary/#LittleEndian"><code>LittleEndian</code></a> now implement this interface. - </p> - <p><!-- https://go.dev/issue/51644 --><!-- CL 400176 --> - Similarly, the new functions - <a href="/pkg/encoding/binary/#AppendUvarint"><code>AppendUvarint</code></a> and - <a href="/pkg/encoding/binary/#AppendVarint"><code>AppendVarint</code></a> - are efficient appending versions of - <a href="/pkg/encoding/binary/#PutUvarint"><code>PutUvarint</code></a> and - <a href="/pkg/encoding/binary/#PutVarint"><code>PutVarint</code></a>. - </p> - </dd> -</dl><!-- encoding/binary --> - -<dl id="encoding/csv"><dt><a href="/pkg/encoding/csv/">encoding/csv</a></dt> - <dd> - <p><!-- https://go.dev/issue/43401 --><!-- CL 405675 --> - The new method - <a href="/pkg/encoding/csv/#Reader.InputOffset"><code>Reader.InputOffset</code></a> - reports the reader's current input position as a byte offset, - analogous to <code>encoding/json</code>'s - <a href="/pkg/encoding/json/#Decoder.InputOffset"><code>Decoder.InputOffset</code></a>. - </p> - </dd> -</dl><!-- encoding/csv --> - -<dl id="encoding/xml"><dt><a href="/pkg/encoding/xml/">encoding/xml</a></dt> - <dd> - <p><!-- https://go.dev/issue/45628 --><!-- CL 311270 --> - The new method - <a href="/pkg/encoding/xml/#Decoder.InputPos"><code>Decoder.InputPos</code></a> - reports the reader's current input position as a line and column, - analogous to <code>encoding/csv</code>'s - <a href="/pkg/encoding/csv/#Decoder.FieldPos"><code>Decoder.FieldPos</code></a>. - </p> - </dd> -</dl><!-- encoding/xml --> - -<dl id="flag"><dt><a href="/pkg/flag/">flag</a></dt> - <dd> - <p><!-- https://go.dev/issue/45754 --><!-- CL 313329 --> - The new function - <a href="/pkg/flag/#TextVar"><code>TextVar</code></a> - defines a flag with a value implementing - <a href="/pkg/encoding/#TextUnmarshaler"><code>encoding.TextUnmarshaler</code></a>, - allowing command-line flag variables to have types such as - <a href="/pkg/math/big/#Int"><code>big.Int</code></a>, - <a href="/pkg/net/netip/#Addr"><code>netip.Addr</code></a>, and - <a href="/pkg/time/#Time"><code>time.Time</code></a>. - </p> - </dd> -</dl><!-- flag --> - -<dl id="fmt"><dt><a href="/pkg/fmt/">fmt</a></dt> - <dd> - <p><!-- https://go.dev/issue/47579 --><!-- CL 406177 --> - The new functions - <a href="/pkg/fmt/#Append"><code>Append</code></a>, - <a href="/pkg/fmt/#Appendf"><code>Appendf</code></a>, and - <a href="/pkg/fmt/#Appendln"><code>Appendln</code></a> - append formatted data to byte slices. - </p> - </dd> -</dl><!-- fmt --> - -<dl id="go/parser"><dt><a href="/pkg/go/parser/">go/parser</a></dt> - <dd> - <p><!-- CL 403696 --> - The parser now recognizes <code>~x</code> as a unary expression with operator - <a href="/pkg/go/token#TILDE">token.TILDE</a>, - allowing better error recovery when a type constraint such as <code>~int</code> is used in an incorrect context. - </p> - </dd> -</dl><!-- go/parser --> - -<dl id="go/types"><dt><a href="/pkg/go/types/">go/types</a></dt> - <dd> - <p><!-- https://go.dev/issue/51682 --><!-- CL 395535 --> - The new methods <a href="/pkg/go/types/#Func.Origin"><code>Func.Origin</code></a> - and <a href="/pkg/go/types/#Var.Origin"><code>Var.Origin</code></a> return the - corresponding <a href="/pkg/go/types/#Object"><code>Object</code></a> of the - generic type for synthetic <a href="/pkg/go/types/#Func"><code>Func</code></a> - and <a href="/pkg/go/types/#Var"><code>Var</code></a> objects created during type - instantiation. - </p> - <p><!-- https://go.dev/issue/52728 --><!-- CL 404885 --> - It is no longer possible to produce an infinite number of distinct-but-identical - <a href="/pkg/go/types/#Named"><code>Named</code></a> type instantiations via - recursive calls to - <a href="/pkg/go/types/#Named.Underlying"><code>Named.Underlying</code></a> or - <a href="/pkg/go/types/#Named.Method"><code>Named.Method</code></a>. - </p> - </dd> -</dl><!-- go/types --> - - -<dl id="hash/maphash"><dt><a href="/pkg/hash/maphash/">hash/maphash</a></dt> - <dd> - <p><!-- https://go.dev/issue/42710 --><!-- CL 392494 --> - The new functions - <a href="/pkg/hash/maphash/#Bytes"><code>Bytes</code></a> - and - <a href="/pkg/hash/maphash/#String"><code>String</code></a> - provide an efficient way hash a single byte slice or string. - They are equivalent to using the more general - <a href="/pkg/hash/maphash/#Hash"><code>Hash</code></a> - with a single write, but they avoid setup overhead for small inputs. - </p> - </dd> -</dl><!-- hash/maphash --> - -<dl id="html/template"><dt><a href="/pkg/html/template/">html/template</a></dt> - <dd> - <p><!-- https://go.dev/issue/46121 --><!-- CL 389156 --> - The type <a href="/pkg/html/template/#FuncMap"><code>FuncMap</code></a> - is now an alias for - <code>text/template</code>'s <a href="/pkg/text/template/#FuncMap"><code>FuncMap</code></a> - instead of its own named type. - This allows writing code that operates on a <code>FuncMap</code> from either setting. - </p> - </dd> -</dl><!-- html/template --> - -<dl id="image/draw"><dt><a href="/pkg/image/draw/">image/draw</a></dt> - <dd> - <p><!-- CL 396795 --> - <a href="/pkg/image/draw/#Draw"><code>Draw</code></a> with the - <a href="/pkg/image/draw/#Src"><code>Src</code></a> operator preserves - non-premultiplied-alpha colors when destination and source images are - both <a href="/pkg/image/#NRGBA"><code>image.NRGBA</code></a> - or both <a href="/pkg/image/#NRGBA64"><code>image.NRGBA64</code></a>. - This reverts a behavior change accidentally introduced by a Go 1.18 - library optimization; the code now matches the behavior in Go 1.17 and earlier. - </p> - </dd> -</dl><!-- image/draw --> - -<dl id="io"><dt><a href="/pkg/io/">io</a></dt> - <dd> - <p><!-- https://go.dev/issue/51566 --><!-- CL 400236 --> - <a href="/pkg/io/#NopCloser"><code>NopCloser</code></a>'s result now implements - <a href="/pkg/io/#WriterTo"><code>WriterTo</code></a> - whenever its input does. - </p> - - <p><!-- https://go.dev/issue/50842 --> - <a href="/pkg/io/#MultiReader"><code>MultiReader</code></a>'s result now implements - <a href="/pkg/io/#WriterTo"><code>WriterTo</code></a> unconditionally. - If any underlying reader does not implement <code>WriterTo</code>, - it is simulated appropriately. - </p> - </dd> -</dl><!-- io --> - -<dl id="mime"><dt><a href="/pkg/mime/">mime</a></dt> - <dd> - <p><!-- CL 406894 --> - On Windows only, the mime package now ignores a registry entry - recording that the extension <code>.js</code> should have MIME - type <code>text/plain</code>. This is a common unintentional - misconfiguration on Windows systems. The effect is - that <code>.js</code> will have the default MIME - type <code>text/javascript; charset=utf-8</code>. - Applications that expect <code>text/plain</code> on Windows must - now explicitly call - <a href="/pkg/mime/#AddExtensionType"><code>AddExtensionType</code></a>. - </p> - </dd> -</dl> - -<dl id="net"><dt><a href="/pkg/net/">net</a></dt> - <dd> - <p><!-- CL 386016 --> - The pure Go resolver will now use EDNS(0) to include a suggested - maximum reply packet length, permitting reply packets to contain - up to 1232 bytes (the previous maximum was 512). - In the unlikely event that this causes problems with a local DNS - resolver, setting the environment variable - <code>GODEBUG=netdns=cgo</code> to use the cgo-based resolver - should work. - Please report any such problems on <a href="/issue/new">the - issue tracker</a>. - </p> - - <p><!-- https://go.dev/issue/51428 --><!-- CL 396877 --> - When a net package function or method returns an "I/O timeout" - error, the error will now satisfy <code>errors.Is(err, - context.DeadlineExceeded)</code>. When a net package function - returns an "operation was canceled" error, the error will now - satisfy <code>errors.Is(err, context.Canceled)</code>. - These changes are intended to make it easier for code to test - for cases in which a context cancellation or timeout causes a net - package function or method to return an error, while preserving - backward compatibility for error messages. - </p> - - <p><!-- https://go.dev/issue/33097 --><!-- CL 400654 --> - <a href="/pkg/net/#Resolver.PreferGo"><code>Resolver.PreferGo</code></a> - is now implemented on Windows and Plan 9. It previously only worked on Unix - platforms. Combined with - <a href="/pkg/net/#Dialer.Resolver"><code>Dialer.Resolver</code></a> and - <a href="/pkg/net/#Resolver.Dial"><code>Resolver.Dial</code></a>, it's now - possible to write portable programs and be in control of all DNS name lookups - when dialing. - </p> - - <p> - The <code>net</code> package now has initial support for the <code>netgo</code> - build tag on Windows. When used, the package uses the Go DNS client (as used - by <code>Resolver.PreferGo</code>) instead of asking Windows for - DNS results. The upstream DNS server it discovers from Windows - may not yet be correct with complex system network configurations, however. - </p> - </dd> -</dl><!-- net --> - -<dl id="net/http"><dt><a href="/pkg/net/http/">net/http</a></dt> - <dd> - <p><!-- CL 269997 --> - <a href="/pkg/net/http/#ResponseWriter"><code>ResponseWriter.WriteHeader</code></a> - now supports sending user-defined 1xx informational headers. - </p> - - <p><!-- CL 361397 --> - The <code>io.ReadCloser</code> returned by - <a href="/pkg/net/http/#MaxBytesReader"><code>MaxBytesReader</code></a> - will now return the defined error type - <a href="/pkg/net/http/#MaxBytesError"><code>MaxBytesError</code></a> - when its read limit is exceeded. - </p> - - <p><!-- CL 375354 --> - The HTTP client will handle a 3xx response without a - <code>Location</code> header by returning it to the caller, - rather than treating it as an error. - </p> - </dd> -</dl><!-- net/http --> - -<dl id="net/url"><dt><a href="/pkg/net/url/">net/url</a></dt> - <dd> - <p><!-- CL 374654 --> - The new - <a href="/pkg/net/url/#JoinPath"><code>JoinPath</code></a> - function and - <a href="/pkg/net/url/#URL.JoinPath"><code>URL.JoinPath</code></a> - method create a new <code>URL</code> by joining a list of path - elements. - </p> - <p><!-- https://go.dev/issue/46059 --> - The <code>URL</code> type now distinguishes between URLs with no - authority and URLs with an empty authority. For example, - <code>http:///path</code> has an empty authority (host), - while <code>http:/path</code> has none. - </p> - <p> - The new <a href="/pkg/net/url/#URL"><code>URL</code></a> field - <code>OmitHost</code> is set to <code>true</code> when a - <code>URL</code> has an empty authority. - </p> - - </dd> -</dl><!-- net/url --> - -<dl id="os/exec"><dt><a href="/pkg/os/exec/">os/exec</a></dt> - <dd> - <p><!-- https://go.dev/issue/50599 --><!-- CL 401340 --> - A <a href="/pkg/os/exec/#Cmd"><code>Cmd</code></a> with a non-empty <code>Dir</code> field - and nil <code>Env</code> now implicitly sets the <code>PWD</code> environment - variable for the subprocess to match <code>Dir</code>. - </p> - <p> - The new method <a href="/pkg/os/exec/#Cmd.Environ"><code>Cmd.Environ</code></a> reports the - environment that would be used to run the command, including the - implicitly set <code>PWD</code> variable. - </p> - </dd> -</dl> <!-- os/exec --> - -<dl id="reflect"><dt><a href="/pkg/reflect/">reflect</a></dt> - <dd> - <p><!-- https://go.dev/issue/47066 --><!-- CL 357331 --> - The method <a href="/pkg/reflect/#Value.Bytes"><code>Value.Bytes</code></a> - now accepts addressable arrays in addition to slices. - </p> - <p><!-- CL 400954 --> - The methods <a href="/pkg/reflect/#Value.Len"><code>Value.Len</code></a> - and <a href="/pkg/reflect/#Value.Cap"><code>Value.Cap</code></a> - now successfully operate on a pointer to an array and return the length of that array, - to match what the <a href="/ref/spec#Length_and_capacity">builtin - <code>len</code> and <code>cap</code> functions do</a>. - </p> - </dd> -</dl><!-- reflect --> - -<dl id="regexp/syntax"><dt><a href="/pkg/regexp/syntax/">regexp/syntax</a></dt> - <dd> - <p><!-- https://go.dev/issue/51684 --><!-- CL 401076 --> - Go 1.18 release candidate 1, Go 1.17.8, and Go 1.16.15 included a security fix - to the regular expression parser, making it reject very deeply nested expressions. - Because Go patch releases do not introduce new API, - the parser returned <a href="/pkg/regexp/syntax/#ErrInternalError"><code>syntax.ErrInternalError</code></a> in this case. - Go 1.19 adds a more specific error, <a href="/pkg/regexp/syntax/#ErrNestingDepth"><code>syntax.ErrNestingDepth</code></a>, - which the parser now returns instead. - </p> - </dd> -</dl><!-- regexp --> - -<dl id="pkg-runtime"><dt><a href="/pkg/runtime/">runtime</a></dt> - <dd> - <p><!-- https://go.dev/issue/51461 --> - The <a href="/pkg/runtime/#GOROOT"><code>GOROOT</code></a> function now returns the empty string - (instead of <code>"go"</code>) when the binary was built with - the <code>-trimpath</code> flag set and the <code>GOROOT</code> - variable is not set in the process environment. - </p> - </dd> -</dl><!-- runtime --> - -<dl id="runtime/metrics"><dt><a href="/pkg/runtime/metrics/">runtime/metrics</a></dt> - <dd> - <p><!-- https://go.dev/issue/47216 --><!-- CL 404305 --> - The new <code>/sched/gomaxprocs:threads</code> - <a href="/pkg/runtime/metrics/#hdr-Supported_metrics">metric</a> reports - the current - <a href="/pkg/runtime/#GOMAXPROCS"><code>runtime.GOMAXPROCS</code></a> - value. - </p> - - <p><!-- https://go.dev/issue/47216 --><!-- CL 404306 --> - The new <code>/cgo/go-to-c-calls:calls</code> - <a href="/pkg/runtime/metrics/#hdr-Supported_metrics">metric</a> - reports the total number of calls made from Go to C. This metric is - identical to the - <a href="/pkg/runtime/#NumCgoCall"><code>runtime.NumCgoCall</code></a> - function. - </p> - - <p><!-- https://go.dev/issue/48409 --><!-- CL 403614 --> - The new <code>/gc/limiter/last-enabled:gc-cycle</code> - <a href="/pkg/runtime/metrics/#hdr-Supported_metrics">metric</a> - reports the last GC cycle when the GC CPU limiter was enabled. See the - <a href="#runtime">runtime notes</a> for details about the GC CPU limiter. - </p> - </dd> -</dl><!-- runtime/metrics --> - -<dl id="runtime/pprof"><dt><a href="/pkg/runtime/pprof/">runtime/pprof</a></dt> - <dd> - <p><!-- https://go.dev/issue/33250 --><!-- CL 387415 --> - Stop-the-world pause times have been significantly reduced when - collecting goroutine profiles, reducing the overall latency impact to the - application. - </p> - - <p><!-- CL 391434 --> - <code>MaxRSS</code> is now reported in heap profiles for all Unix - operating systems (it was previously only reported for - <code>GOOS=android</code>, <code>darwin</code>, <code>ios</code>, and - <code>linux</code>). - </p> - </dd> -</dl><!-- runtime/pprof --> - -<dl id="runtime/race"><dt><a href="/pkg/runtime/race/">runtime/race</a></dt> - <dd> - <p><!-- https://go.dev/issue/49761 --><!-- CL 333529 --> - The race detector has been upgraded to use thread sanitizer - version v3 on all supported platforms - except <code>windows/amd64</code> - and <code>openbsd/amd64</code>, which remain on v2. - Compared to v2, it is now typically 1.5x to 2x faster, uses half - as much memory, and it supports an unlimited number of - goroutines. - On Linux, the race detector now requires at least glibc version - 2.17 and GNU binutils 2.26. - </p> - - <p><!-- CL 336549 --> - The race detector is now supported on <code>GOARCH=s390x</code>. - </p> - - <p><!-- https://go.dev/issue/52090 --> - Race detector support for <code>openbsd/amd64</code> has been - removed from thread sanitizer upstream, so it is unlikely to - ever be updated from v2. - </p> - </dd> -</dl><!-- runtime/race --> - -<dl id="runtime/trace"><dt><a href="/pkg/runtime/trace/">runtime/trace</a></dt> - <dd> - <p><!-- CL 400795 --> - When tracing and the - <a href="/pkg/runtime/pprof#StartCPUProfile">CPU profiler</a> are - enabled simultaneously, the execution trace includes CPU profile - samples as instantaneous events. - </p> - </dd> -</dl><!-- runtime/trace --> - -<dl id="sort"><dt><a href="/pkg/sort/">sort</a></dt> - <dd> - <p><!-- CL 371574 --> - The sorting algorithm has been rewritten to use - <a href="https://arxiv.org/pdf/2106.05123.pdf">pattern-defeating quicksort</a>, which - is faster for several common scenarios. - </p> - <p><!-- https://go.dev/issue/50340 --><!-- CL 396514 --> - The new function - <a href="/pkg/sort/#Find"><code>Find</code></a> - is like - <a href="/pkg/sort/#Search"><code>Search</code></a> - but often easier to use: it returns an additional boolean reporting whether an equal value was found. - </p> - </dd> -</dl><!-- sort --> - -<dl id="strconv"><dt><a href="/pkg/strconv/">strconv</a></dt> - <dd> - <p><!-- CL 397255 --> - <a href="/pkg/strconv/#Quote"><code>Quote</code></a> - and related functions now quote the rune U+007F as <code>\x7f</code>, - not <code>\u007f</code>, - for consistency with other ASCII values. - </p> - </dd> -</dl><!-- strconv --> - -<dl id="syscall"><dt><a href="/pkg/syscall/">syscall</a></dt> - <dd> - <p><!-- https://go.dev/issue/51192 --><!-- CL 385796 --> - On PowerPC (<code>GOARCH=ppc64</code>, <code>ppc64le</code>), - <a href="/pkg/syscall/#Syscall"><code>Syscall</code></a>, - <a href="/pkg/syscall/#Syscall6"><code>Syscall6</code></a>, - <a href="/pkg/syscall/#RawSyscall"><code>RawSyscall</code></a>, and - <a href="/pkg/syscall/#RawSyscall6"><code>RawSyscall6</code></a> - now always return 0 for return value <code>r2</code> instead of an - undefined value. - </p> - - <p><!-- CL 391434 --> - On AIX and Solaris, <a href="/pkg/syscall/#Getrusage"><code>Getrusage</code></a> is now defined. - </p> - </dd> -</dl><!-- syscall --> - -<dl id="time"><dt><a href="/pkg/time/">time</a></dt> - <dd> - <p><!-- https://go.dev/issue/51414 --><!-- CL 393515 --> - The new method - <a href="/pkg/time/#Duration.Abs"><code>Duration.Abs</code></a> - provides a convenient and safe way to take the absolute value of a duration, - converting −2⁶³ to 2⁶³−1. - (This boundary case can happen as the result of subtracting a recent time from the zero time.) - </p> - <p><!-- https://go.dev/issue/50062 --><!-- CL 405374 --> - The new method - <a href="/pkg/time/#Time.ZoneBounds"><code>Time.ZoneBounds</code></a> - returns the start and end times of the time zone in effect at a given time. - It can be used in a loop to enumerate all the known time zone transitions at a given location. - </p> - </dd> -</dl><!-- time --> - -<!-- Silence these false positives from x/build/cmd/relnote: --> -<!-- CL 382460 --> -<!-- CL 384154 --> -<!-- CL 384554 --> -<!-- CL 392134 --> -<!-- CL 392414 --> -<!-- CL 396215 --> -<!-- CL 403058 --> -<!-- CL 410133 --> -<!-- https://go.dev/issue/27837 --> -<!-- https://go.dev/issue/38340 --> -<!-- https://go.dev/issue/42516 --> -<!-- https://go.dev/issue/45713 --> -<!-- https://go.dev/issue/46654 --> -<!-- https://go.dev/issue/48257 --> -<!-- https://go.dev/issue/50447 --> -<!-- https://go.dev/issue/50720 --> -<!-- https://go.dev/issue/50792 --> -<!-- https://go.dev/issue/51115 --> -<!-- https://go.dev/issue/51447 --> |