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diff --git a/doc/go1.14.html b/doc/go1.14.html deleted file mode 100644 index 410e0cbf7c..0000000000 --- a/doc/go1.14.html +++ /dev/null @@ -1,924 +0,0 @@ -<!--{ - "Title": "Go 1.14 Release Notes", - "Path": "/doc/go1.14" -}--> - -<!-- -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">Introduction to Go 1.14</h2> - -<p> - The latest Go release, version 1.14, arrives six months after <a href="go1.13">Go 1.13</a>. - Most of its changes are in the implementation of the toolchain, runtime, and libraries. - As always, the release maintains the Go 1 <a href="/doc/go1compat.html">promise of compatibility</a>. - We expect almost all Go programs to continue to compile and run as before. -</p> - -<p> - Module support in the <code>go</code> command is now ready for production use, - and we encourage all users to <a href="https://blog.golang.org/migrating-to-go-modules">migrate to Go - modules for dependency management</a>. If you are unable to migrate due to a problem in the Go - toolchain, please ensure that the problem has an - <a href="https://golang.org/issue?q=is%3Aissue+is%3Aopen+label%3Amodules">open issue</a> - filed. (If the issue is not on the <code>Go1.15</code> milestone, please let us - know why it prevents you from migrating so that we can prioritize it - appropriately.) -</p> - -<h2 id="language">Changes to the language</h2> - -<p> - Per the <a href="https://github.com/golang/proposal/blob/master/design/6977-overlapping-interfaces.md">overlapping interfaces proposal</a>, - Go 1.14 now permits embedding of interfaces with overlapping method sets: - methods from an embedded interface may have the same names and identical signatures - as methods already present in the (embedding) interface. This solves problems that typically - (but not exclusively) occur with diamond-shaped embedding graphs. - Explicitly declared methods in an interface must remain - <a href="https://tip.golang.org/ref/spec#Uniqueness_of_identifiers">unique</a>, as before. -</p> - -<h2 id="ports">Ports</h2> - -<h3 id="darwin">Darwin</h3> - -<p> - Go 1.14 is the last release that will run on macOS 10.11 El Capitan. - Go 1.15 will require macOS 10.12 Sierra or later. -</p> - -<p><!-- golang.org/issue/34749 --> - Go 1.14 is the last Go release to support 32-bit binaries on - macOS (the <code>darwin/386</code> port). They are no longer - supported by macOS, starting with macOS 10.15 (Catalina). - Go continues to support the 64-bit <code>darwin/amd64</code> port. -</p> - -<p><!-- golang.org/issue/34751 --> - Go 1.14 will likely be the last Go release to support 32-bit - binaries on iOS, iPadOS, watchOS, and tvOS - (the <code>darwin/arm</code> port). Go continues to support the - 64-bit <code>darwin/arm64</code> port. -</p> - -<h3 id="windows">Windows</h3> - -<p><!-- CL 203601 --> - Go binaries on Windows now - have <a href="https://docs.microsoft.com/en-us/windows/win32/memory/data-execution-prevention">DEP - (Data Execution Prevention)</a> enabled. -</p> - -<p><!-- CL 202439 --> - On Windows, creating a file - via <a href="/pkg/os#CreateFile"><code>os.OpenFile</code></a> with - the <a href="/pkg/os/#O_CREATE"><code>os.O_CREATE</code></a> flag, or - via <a href="/pkg/syscall#Open"><code>syscall.Open</code></a> with - the <a href="/pkg/syscall#O_CREAT"><code>syscall.O_CREAT</code></a> - flag, will now create the file as read-only if the - bit <code>0o200</code> (owner write permission) is not set in the - permission argument. This makes the behavior on Windows more like - that on Unix systems. -</p> - -<h3 id="wasm">WebAssembly</h3> - -<p><!-- CL 203600 --> - JavaScript values referenced from Go via <code>js.Value</code> - objects can now be garbage collected. -</p> - -<p><!-- CL 203600 --> - <code>js.Value</code> values can no longer be compared using - the <code>==</code> operator, and instead must be compared using - their <code>Equal</code> method. -</p> - -<p><!-- CL 203600 --> - <code>js.Value</code> now - has <code>IsUndefined</code>, <code>IsNull</code>, - and <code>IsNaN</code> methods. -</p> - -<h3 id="riscv">RISC-V</h3> - -<p><!-- Issue 27532 --> - Go 1.14 contains experimental support for 64-bit RISC-V on Linux - (<code>GOOS=linux</code>, <code>GOARCH=riscv64</code>). Be aware - that performance, assembly syntax stability, and possibly - correctness are a work in progress. -</p> - -<h3 id="freebsd">FreeBSD</h3> - -<p><!-- CL 199919 --> - Go now supports the 64-bit ARM architecture on FreeBSD 12.0 or later (the - <code>freebsd/arm64</code> port). -</p> - -<h3 id="nacl">Native Client (NaCl)</h3> - -<p><!-- golang.org/issue/30439 --> - As <a href="go1.13#ports">announced</a> in the Go 1.13 release notes, - Go 1.14 drops support for the Native Client platform (<code>GOOS=nacl</code>). -</p> - -<h3 id="illumos">Illumos</h3> - -<p><!-- CL 203758 --> - The runtime now respects zone CPU caps - (the <code>zone.cpu-cap</code> resource control) - for <code>runtime.NumCPU</code> and the default value - of <code>GOMAXPROCS</code>. -</p> - -<h2 id="tools">Tools</h2> - -<h3 id="go-command">Go command</h3> - -<h4 id="vendor">Vendoring</h4> -<!-- golang.org/issue/33848 --> - -<p> - When the main module contains a top-level <code>vendor</code> directory and - its <code>go.mod</code> file specifies <code>go</code> <code>1.14</code> or - higher, the <code>go</code> command now defaults to <code>-mod=vendor</code> - for operations that accept that flag. A new value for that flag, - <code>-mod=mod</code>, causes the <code>go</code> command to instead load - modules from the module cache (as when no <code>vendor</code> directory is - present). -</p> - -<p> - When <code>-mod=vendor</code> is set (explicitly or by default), the - <code>go</code> command now verifies that the main module's - <code>vendor/modules.txt</code> file is consistent with its - <code>go.mod</code> file. -</p> - -<p> - <code>go</code> <code>list</code> <code>-m</code> no longer silently omits - transitive dependencies that do not provide packages in - the <code>vendor</code> directory. It now fails explicitly if - <code>-mod=vendor</code> is set and information is requested for a module not - mentioned in <code>vendor/modules.txt</code>. -</p> - -<h4 id="go-flags">Flags</h4> - -<p><!-- golang.org/issue/32502, golang.org/issue/30345 --> - The <code>go</code> <code>get</code> command no longer accepts - the <code>-mod</code> flag. Previously, the flag's setting either - <a href="https://golang.org/issue/30345">was ignored</a> or - <a href="https://golang.org/issue/32502">caused the build to fail</a>. -</p> - -<p><!-- golang.org/issue/33326 --> - <code>-mod=readonly</code> is now set by default when the <code>go.mod</code> - file is read-only and no top-level <code>vendor</code> directory is present. -</p> - -<p><!-- golang.org/issue/31481 --> - <code>-modcacherw</code> is a new flag that instructs the <code>go</code> - command to leave newly-created directories in the module cache at their - default permissions rather than making them read-only. - The use of this flag makes it more likely that tests or other tools will - accidentally add files not included in the module's verified checksum. - However, it allows the use of <code>rm</code> <code>-rf</code> - (instead of <code>go</code> <code>clean</code> <code>-modcache</code>) - to remove the module cache. -</p> - -<p><!-- golang.org/issue/34506 --> - <code>-modfile=file</code> is a new flag that instructs the <code>go</code> - command to read (and possibly write) an alternate <code>go.mod</code> file - instead of the one in the module root directory. A file - named <code>go.mod</code> must still be present in order to determine the - module root directory, but it is not accessed. When <code>-modfile</code> is - specified, an alternate <code>go.sum</code> file is also used: its path is - derived from the <code>-modfile</code> flag by trimming the <code>.mod</code> - extension and appending <code>.sum</code>. -</p> - -<h4 id="go-env-vars">Environment variables</h4> - -<p><!-- golang.org/issue/32966 --> - <code>GOINSECURE</code> is a new environment variable that instructs - the <code>go</code> command to not require an HTTPS connection, and to skip - certificate validation, when fetching certain modules directly from their - origins. Like the existing <code>GOPRIVATE</code> variable, the value - of <code>GOINSECURE</code> is a comma-separated list of glob patterns. -</p> - -<h4 id="commands-outside-modules">Commands outside modules</h4> - -<p><!-- golang.org/issue/32027 --> - When module-aware mode is enabled explicitly (by setting - <code>GO111MODULE=on</code>), most module commands have more - limited functionality if no <code>go.mod</code> file is present. For - example, <code>go</code> <code>build</code>, - <code>go</code> <code>run</code>, and other build commands can only build - packages in the standard library and packages specified as <code>.go</code> - files on the command line. -</p> - -<p> - Previously, the <code>go</code> command would resolve each package path - to the latest version of a module but would not record the module path - or version. This resulted in <a href="https://golang.org/issue/32027">slow, - non-reproducible builds</a>. -</p> - -<p> - <code>go</code> <code>get</code> continues to work as before, as do - <code>go</code> <code>mod</code> <code>download</code> and - <code>go</code> <code>list</code> <code>-m</code> with explicit versions. -</p> - -<h4 id="incompatible-versions"><code>+incompatible</code> versions</h4> -<!-- golang.org/issue/34165 --> - -<p> - If the latest version of a module contains a <code>go.mod</code> file, - <code>go</code> <code>get</code> will no longer upgrade to an - <a href="/cmd/go/#hdr-Module_compatibility_and_semantic_versioning">incompatible</a> - major version of that module unless such a version is requested explicitly - or is already required. - <code>go</code> <code>list</code> also omits incompatible major versions - for such a module when fetching directly from version control, but may - include them if reported by a proxy. -</p> - - -<h4 id="go.mod"><code>go.mod</code> file maintenance</h4> -<!-- golang.org/issue/34822 --> - -<p> - <code>go</code> commands other than - <code>go</code> <code>mod</code> <code>tidy</code> no longer - remove a <code>require</code> directive that specifies a version of an indirect dependency - that is already implied by other (transitive) dependencies of the main - module. -</p> - -<p> - <code>go</code> commands other than - <code>go</code> <code>mod</code> <code>tidy</code> no longer - edit the <code>go.mod</code> file if the changes are only cosmetic. -</p> - -<p> - When <code>-mod=readonly</code> is set, <code>go</code> commands will no - longer fail due to a missing <code>go</code> directive or an erroneous - <code>// indirect</code> comment. -</p> - -<h4 id="module-downloading">Module downloading</h4> - -<p><!-- golang.org/issue/26092 --> - The <code>go</code> command now supports Subversion repositories in module mode. -</p> - -<p><!-- golang.org/issue/30748 --> - The <code>go</code> command now includes snippets of plain-text error messages - from module proxies and other HTTP servers. - An error message will only be shown if it is valid UTF-8 and consists of only - graphic characters and spaces. -</p> - -<h4 id="go-test">Testing</h4> - -<p><!-- golang.org/issue/24929 --> - <code>go test -v</code> now streams <code>t.Log</code> output as it happens, - rather than at the end of all tests. -</p> - -<h2 id="runtime">Runtime</h2> - -<p><!-- CL 190098 --> - This release improves the performance of most uses - of <code>defer</code> to incur almost zero overhead compared to - calling the deferred function directly. - As a result, <code>defer</code> can now be used in - performance-critical code without overhead concerns. -</p> - -<p><!-- CL 201760, CL 201762 and many others --> - Goroutines are now asynchronously preemptible. - As a result, loops without function calls no longer potentially - deadlock the scheduler or significantly delay garbage collection. - This is supported on all platforms except <code>windows/arm</code>, - <code>darwin/arm</code>, <code>js/wasm</code>, and - <code>plan9/*</code>. -</p> - -<p> - A consequence of the implementation of preemption is that on Unix - systems, including Linux and macOS systems, programs built with Go - 1.14 will receive more signals than programs built with earlier - releases. - This means that programs that use packages - like <a href="/pkg/syscall/"><code>syscall</code></a> - or <a href="https://godoc.org/golang.org/x/sys/unix"><code>golang.org/x/sys/unix</code></a> - will see more slow system calls fail with <code>EINTR</code> errors. - Those programs will have to handle those errors in some way, most - likely looping to try the system call again. For more - information about this - see <a href="http://man7.org/linux/man-pages/man7/signal.7.html"><code>man - 7 signal</code></a> for Linux systems or similar documentation for - other systems. -</p> - -<p><!-- CL 201765, CL 195701 and many others --> - The page allocator is more efficient and incurs significantly less - lock contention at high values of <code>GOMAXPROCS</code>. - This is most noticeable as lower latency and higher throughput for - large allocations being done in parallel and at a high rate. -</p> - -<p><!-- CL 171844 and many others --> - Internal timers, used by - <a href="/pkg/time/#After"><code>time.After</code></a>, - <a href="/pkg/time/#Tick"><code>time.Tick</code></a>, - <a href="/pkg/net/#Conn"><code>net.Conn.SetDeadline</code></a>, - and friends, are more efficient, with less lock contention and fewer - context switches. - This is a performance improvement that should not cause any user - visible changes. -</p> - -<h2 id="compiler">Compiler</h2> - -<p><!-- CL 162237 --> - This release adds <code>-d=checkptr</code> as a compile-time option - for adding instrumentation to check that Go code is following - <code>unsafe.Pointer</code> safety rules dynamically. - This option is enabled by default (except on Windows) with - the <code>-race</code> or <code>-msan</code> flags, and can be - disabled with <code>-gcflags=all=-d=checkptr=0</code>. - Specifically, <code>-d=checkptr</code> checks the following: -</p> - -<ol> - <li> - When converting <code>unsafe.Pointer</code> to <code>*T</code>, - the resulting pointer must be aligned appropriately - for <code>T</code>. - </li> - <li> - If the result of pointer arithmetic points into a Go heap object, - one of the <code>unsafe.Pointer</code>-typed operands must point - into the same object. - </li> -</ol> - -<p> - Using <code>-d=checkptr</code> is not currently recommended on - Windows because it causes false alerts in the standard library. -</p> - -<p><!-- CL 204338 --> - The compiler can now emit machine-readable logs of key optimizations - using the <code>-json</code> flag, including inlining, escape - analysis, bounds-check elimination, and nil-check elimination. -</p> - -<p><!-- CL 196959 --> - Detailed escape analysis diagnostics (<code>-m=2</code>) now work again. - This had been dropped from the new escape analysis implementation in - the previous release. -</p> - -<p><!-- CL 196217 --> - All Go symbols in macOS binaries now begin with an underscore, - following platform conventions. -</p> - -<p><!-- CL 202117 --> - This release includes experimental support for compiler-inserted - coverage instrumentation for fuzzing. - See <a href="https://golang.org/issue/14565">issue 14565</a> for more - details. - This API may change in future releases. -</p> - -<p><!-- CL 174704 --><!-- CL 196784 --> - Bounds check elimination now uses information from slice creation and can - eliminate checks for indexes with types smaller than <code>int</code>. -</p> - -<h2 id="library">Core library</h2> - -<h3 id="hash/maphash">New byte sequence hashing package</h3> - -<p> <!-- golang.org/issue/28322, CL 186877 --> - Go 1.14 includes a new package, - <a href="/pkg/hash/maphash/"><code>hash/maphash</code></a>, - which provides hash functions on byte sequences. - These hash functions are intended to be used to implement hash tables or - other data structures that need to map arbitrary strings or byte - sequences to a uniform distribution on unsigned 64-bit integers. -</p> -<p> - The hash functions are collision-resistant but not cryptographically secure. -</p> -<p> - The hash value of a given byte sequence is consistent within a - single process, but will be different in different processes. -</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. -</p> - -<dl id="crypto/tls"><dt><a href="/pkg/crypto/tls/">crypto/tls</a></dt> - <dd> - <p><!-- CL 191976 --> - Support for SSL version 3.0 (SSLv3) has been removed. Note that SSLv3 is the - <a href="https://tools.ietf.org/html/rfc7568">cryptographically broken</a> - protocol predating TLS. - </p> - - <p><!-- CL 191999 --> - TLS 1.3 can't be disabled via the <code>GODEBUG</code> environment - variable anymore. Use the - <a href="/pkg/crypto/tls/#Config.MaxVersion"><code>Config.MaxVersion</code></a> - field to configure TLS versions. - </p> - - <p><!-- CL 205059 --> - When multiple certificate chains are provided through the - <a href="/pkg/crypto/tls/#Config.Certificates"><code>Config.Certificates</code></a> - field, the first one compatible with the peer is now automatically - selected. This allows for example providing an ECDSA and an RSA - certificate, and letting the package automatically select the best one. - Note that the performance of this selection is going to be poor unless the - <a href="/pkg/crypto/tls/#Certificate.Leaf"><code>Certificate.Leaf</code></a> - field is set. The - <a href="/pkg/crypto/tls/#Config.NameToCertificate"><code>Config.NameToCertificate</code></a> - field, which only supports associating a single certificate with - a give name, is now deprecated and should be left as <code>nil</code>. - Similarly the - <a href="/pkg/crypto/tls/#Config.BuildNameToCertificate"><code>Config.BuildNameToCertificate</code></a> - method, which builds the <code>NameToCertificate</code> field - from the leaf certificates, is now deprecated and should not be - called. - </p> - - <p><!-- CL 175517 --> - The new <a href="/pkg/crypto/tls/#CipherSuites"><code>CipherSuites</code></a> - and <a href="/pkg/crypto/tls/#InsecureCipherSuites"><code>InsecureCipherSuites</code></a> - functions return a list of currently implemented cipher suites. - The new <a href="/pkg/crypto/tls/#CipherSuiteName"><code>CipherSuiteName</code></a> - function returns a name for a cipher suite ID. - </p> - - <p><!-- CL 205058, 205057 --> - The new <a href="/pkg/crypto/tls/#ClientHelloInfo.SupportsCertificate"> - <code>(*ClientHelloInfo).SupportsCertificate</code></a> and - <a href="/pkg/crypto/tls/#CertificateRequestInfo.SupportsCertificate"> - <code>(*CertificateRequestInfo).SupportsCertificate</code></a> - methods expose whether a peer supports a certain certificate. - </p> - - <p><!-- CL 174329 --> - The <code>tls</code> package no longer supports the legacy Next Protocol - Negotiation (NPN) extension and now only supports ALPN. In previous - releases it supported both. There are no API changes and applications - should function identically as before. Most other clients and servers have - already removed NPN support in favor of the standardized ALPN. - </p> - - <p><!-- CL 205063, 205062 --> - RSA-PSS signatures are now used when supported in TLS 1.2 handshakes. This - won't affect most applications, but custom - <a href="/pkg/crypto/tls/#Certificate.PrivateKey"><code>Certificate.PrivateKey</code></a> - implementations that don't support RSA-PSS signatures will need to use the new - <a href="/pkg/crypto/tls/#Certificate.SupportedSignatureAlgorithms"> - <code>Certificate.SupportedSignatureAlgorithms</code></a> - field to disable them. - </p> - - <p><!-- CL 205059, 205059 --> - <a href="/pkg/crypto/tls/#Config.Certificates"><code>Config.Certificates</code></a> and - <a href="/pkg/crypto/tls/#Config.GetCertificate"><code>Config.GetCertificate</code></a> - can now both be nil if - <a href="/pkg/crypto/tls/#Config.GetConfigForClient"><code>Config.GetConfigForClient</code></a> - is set. If the callbacks return neither certificates nor an error, the - <code>unrecognized_name</code> is now sent. - </p> - - <p><!-- CL 205058 --> - The new <a href="/pkg/crypto/tls/#CertificateRequestInfo.Version"><code>CertificateRequestInfo.Version</code></a> - field provides the TLS version to client certificates callbacks. - </p> - - <p><!-- CL 205068 --> - The new <code>TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256</code> and - <code>TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256</code> constants use - the final names for the cipher suites previously referred to as - <code>TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305</code> and - <code>TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305</code>. - </p> - </dd> -</dl><!-- crypto/tls --> - -<dl id="crypto/x509"><dt><a href="/pkg/crypto/x509/">crypto/x509</a></dt> - <dd> - <p><!-- CL 204046 --> - <a href="/pkg/crypto/x509/#Certificate.CreateCRL"><code>Certificate.CreateCRL</code></a> - now supports Ed25519 issuers. - </p> - </dd> -</dl> - -<dl id="debug/dwarf"><dt><a href="/pkg/debug/dwarf/">debug/dwarf</a></dt> - <dd> - <p><!-- CL 175138 --> - The <code>debug/dwarf</code> package now supports reading DWARF - version 5. - </p> - <p> - The new - method <a href="/pkg/debug/dwarf/#Data.AddSection"><code>(*Data).AddSection</code></a> - supports adding arbitrary new DWARF sections from the input file - to the DWARF <code>Data</code>. - </p> - - <p><!-- CL 192698 --> - The new - method <a href="/pkg/debug/dwarf/#Reader.ByteOrder"><code>(*Reader).ByteOrder</code></a> - returns the byte order of the current compilation unit. - This may be used to interpret attributes that are encoded in the - native ordering, such as location descriptions. - </p> - - <p><!-- CL 192699 --> - The new - method <a href="/pkg/debug/dwarf/#LineReader.Files"><code>(*LineReader).Files</code></a> - returns the file name table from a line reader. - This may be used to interpret the value of DWARF attributes such - as <code>AttrDeclFile</code>. - </p> - </dd> -</dl><!-- debug/dwarf --> - -<dl id="encoding/asn1"><dt><a href="/pkg/encoding/asn1/">encoding/asn1</a></dt> - <dd> - <p><!-- CL 126624 --> - <a href="/pkg/encoding/asn1/#Unmarshal"><code>Unmarshal</code></a> - now supports ASN.1 string type BMPString, represented by the new - <a href="/pkg/encoding/asn1/#TagBMPString"><code>TagBMPString</code></a> - constant. - </p> - </dd> -</dl><!-- encoding/asn1 --> - -<dl id="encoding/json"><dt><a href="/pkg/encoding/json/">encoding/json</a></dt> - <dd> - <p><!-- CL 200677 --> - The <a href="/pkg/encoding/json/#Decoder"><code>Decoder</code></a> - type supports a new - method <a href="/pkg/encoding/json/#Decoder.InputOffset"><code>InputOffset</code></a> - that returns the input stream byte offset of the current - decoder position. - </p> - - <p><!-- CL 200217 --> - <a href="/pkg/encoding/json/#Compact"><code>Compact</code></a> no longer - escapes the <code>U+2028</code> and <code>U+2029</code> characters, which - was never a documented feature. For proper escaping, see <a - href="/pkg/encoding/json/#HTMLEscape"><code>HTMLEscape</code></a>. - </p> - - <p><!-- CL 195045 --> - <a href="/pkg/encoding/json/#Number"><code>Number</code></a> no longer - accepts invalid numbers, to follow the documented behavior more closely. - If a program needs to accept invalid numbers like the empty string, - consider wrapping the type with <a href="/pkg/encoding/json/#Unmarshaler"><code>Unmarshaler</code></a>. - </p> - - <p><!-- CL 200237 --> - <a href="/pkg/encoding/json/#Unmarshal"><code>Unmarshal</code></a> - can now support map keys with string underlying type which implement - <a href="/pkg/encoding/#TextUnmarshaler"><code>encoding.TextUnmarshaler</code></a>. - </p> - </dd> -</dl><!-- encoding/json --> - -<dl id="go/build"><dt><a href="/pkg/go/build/">go/build</a></dt> - <dd> - <p><!-- CL 203820, 211657 --> - The <a href="/pkg/go/build/#Context"><code>Context</code></a> - type has a new field <code>Dir</code> which may be used to set - the working directory for the build. - The default is the current directory of the running process. - In module mode, this is used to locate the main module. - </p> - </dd> -</dl><!-- go/build --> - -<dl id="go/doc"><dt><a href="/pkg/go/doc/">go/doc</a></dt> - <dd> - <p><!-- CL 204830 --> - The new - function <a href="/pkg/go/doc/#NewFromFiles"><code>NewFromFiles</code></a> - computes package documentation from a list - of <code>*ast.File</code>'s and associates examples with the - appropriate package elements. - The new information is available in a new <code>Examples</code> - field - in the <a href="/pkg/go/doc/#Package"><code>Package</code></a>, <a href="/pkg/go/doc/#Type"><code>Type</code></a>, - and <a href="/pkg/go/doc/#Func"><code>Func</code></a> types, and a - new <a href="/pkg/go/doc/#Example.Suffix"><code>Suffix</code></a> - field in - the <a href="/pkg/go/doc/#Example"><code>Example</code></a> - type. - </p> - </dd> -</dl><!-- go/doc --> - -<dl id="io/ioutil"><dt><a href="/pkg/io/ioutil/">io/ioutil</a></dt> - <dd> - <p><!-- CL 198488 --> - <a href="/pkg/io/ioutil/#TempDir"><code>TempDir</code></a> can now create directories - whose names have predictable prefixes and suffixes. - As with <a href="/pkg/io/ioutil/#TempFile"><code>TempFile</code></a>, if the pattern - contains a '*', the random string replaces the last '*'. - </p> - </dd> -</dl> - -<dl id="log"><dt><a href="/pkg/log/">log</a></dt> - <dd> - <p><!-- CL 186182 --> - The - new <a href="https://tip.golang.org/pkg/log/#pkg-constants"><code>Lmsgprefix</code></a> - flag may be used to tell the logging functions to emit the - optional output prefix immediately before the log message rather - than at the start of the line. - </p> - </dd> -</dl><!-- log --> - -<dl id="math"><dt><a href="/pkg/math/">math</a></dt> - <dd> - <p><!-- CL 127458 --> - The new <a href="/pkg/math/#FMA"><code>FMA</code></a> function - computes <code>x*y+z</code> in floating point with no - intermediate rounding of the <code>x*y</code> - computation. Several architectures implement this computation - using dedicated hardware instructions for additional performance. - </p> - </dd> -</dl><!-- math --> - -<dl id="math/big"><dt><a href="/pkg/math/big/">math/big</a></dt> - <dd> - <p><!-- CL 164972 --> - The <a href="/pkg/math/big/#Int.GCD"><code>GCD</code></a> method - now allows the inputs <code>a</code> and <code>b</code> to be - zero or negative. - </p> - </dd> -</dl><!-- math/big --> - -<dl id="math/bits"><dt><a href="/pkg/math/bits/">math/bits</a></dt> - <dd> - <p><!-- CL 197838 --> - The new functions - <a href="/pkg/math/bits/#Rem"><code>Rem</code></a>, - <a href="/pkg/math/bits/#Rem32"><code>Rem32</code></a>, and - <a href="/pkg/math/bits/#Rem64"><code>Rem64</code></a> - support computing a remainder even when the quotient overflows. - </p> - </dd> -</dl><!-- math/bits --> - -<dl id="mime"><dt><a href="/pkg/mime/">mime</a></dt> - <dd> - <p><!-- CL 186927 --> - The default type of <code>.js</code> and <code>.mjs</code> files - is now <code>text/javascript</code> rather - than <code>application/javascript</code>. - This is in accordance - with <a href="https://datatracker.ietf.org/doc/draft-ietf-dispatch-javascript-mjs/">an - IETF draft</a> that treats <code>application/javascript</code> as obsolete. - </p> - </dd> -</dl><!-- mime --> - -<dl id="mime/multipart"><dt><a href="/pkg/mime/multipart/">mime/multipart</a></dt> - <dd> - <p> - The - new <a href="/pkg/mime/multipart/#Reader"><code>Reader</code></a> - method <a href="/pkg/mime/multipart/#Reader.NextRawPart"><code>NextRawPart</code></a> - supports fetching the next MIME part without transparently - decoding <code>quoted-printable</code> data. - </p> - </dd> -</dl><!-- mime/multipart --> - -<dl id="net/http"><dt><a href="/pkg/net/http/">net/http</a></dt> - <dd> - <p><!-- CL 200760 --> - The new <a href="/pkg/net/http/#Header"><code>Header</code></a> - method <a href="/pkg/net/http/#Header.Values"><code>Values</code></a> - can be used to fetch all values associated with a - canonicalized key. - </p> - - <p><!-- CL 61291 --> - The - new <a href="/pkg/net/http/#Transport"><code>Transport</code></a> - field <a href="/pkg/net/http/#Transport.DialTLSContext"><code>DialTLSContext</code></a> - can be used to specify an optional dial function for creating - TLS connections for non-proxied HTTPS requests. - This new field can be used instead - of <a href="/pkg/net/http/#Transport.DialTLS"><code>DialTLS</code></a>, - which is now considered deprecated; <code>DialTLS</code> will - continue to work, but new code should - use <code>DialTLSContext</code>, which allows the transport to - cancel dials as soon as they are no longer needed. - </p> - - <p><!-- CL 192518, CL 194218 --> - On Windows, <a href="/pkg/net/http/#ServeFile"><code>ServeFile</code></a> now correctly - serves files larger than 2GB. - </p> - </dd> -</dl><!-- net/http --> - -<dl id="net/http/httptest"><dt><a href="/pkg/net/http/httptest/">net/http/httptest</a></dt> - <dd> - <p><!-- CL 201557 --> - The - new <a href="/pkg/net/http/httptest/#Server"><code>Server</code></a> - field <a href="/pkg/net/http/httptest/#Server.EnableHTTP2"><code>EnableHTTP2</code></a> - supports enabling HTTP/2 on the test server. - </p> - </dd> -</dl><!-- net/http/httptest --> - -<dl id="net/textproto"><dt><a href="/pkg/net/textproto/">net/textproto</a></dt> - <dd> - <p><!-- CL 200760 --> - The - new <a href="/pkg/net/textproto/#MIMEHeader"><code>MIMEHeader</code></a> - method <a href="/pkg/net/textproto/#MIMEHeader.Values"><code>Values</code></a> - can be used to fetch all values associated with a canonicalized - key. - </p> - </dd> -</dl><!-- net/textproto --> - -<dl id="net/url"><dt><a href="/pkg/net/url/">net/url</a></dt> - <dd> - <p><!-- CL 185117 --> - When parsing of a URL fails - (for example by <a href="/pkg/net/url/#Parse"><code>Parse</code></a> - or <a href="/pkg/net/url/#ParseRequestURI"><code>ParseRequestURI</code></a>), - the resulting <a href="/pkg/net/url/#Error.Error"><code>Error</code></a> message - will now quote the unparsable URL. - This provides clearer structure and consistency with other parsing errors. - </p> - </dd> -</dl><!-- net/url --> - -<dl id="os/signal"><dt><a href="/pkg/os/signal/">os/signal</a></dt> - <dd> - <p><!-- CL 187739 --> - On Windows, - the <code>CTRL_CLOSE_EVENT</code>, <code>CTRL_LOGOFF_EVENT</code>, - and <code>CTRL_SHUTDOWN_EVENT</code> events now generate - a <code>syscall.SIGTERM</code> signal, similar to how Control-C - and Control-Break generate a <code>syscall.SIGINT</code> signal. - </p> - </dd> -</dl><!-- os/signal --> - -<dl id="plugin"><dt><a href="/pkg/plugin/">plugin</a></dt> - <dd> - <p><!-- CL 191617 --> - The <code>plugin</code> package now supports <code>freebsd/amd64</code>. - </p> - </dd> -</dl><!-- plugin --> - -<dl id="reflect"><dt><a href="/pkg/reflect/">reflect</a></dt> - <dd> - <p><!-- CL 85661 --> - <a href="/pkg/reflect#StructOf"><code>StructOf</code></a> now - supports creating struct types with unexported fields, by - setting the <code>PkgPath</code> field in - a <code>StructField</code> element. - </p> - </dd> -</dl><!-- reflect --> - -<dl id="pkg-runtime"><dt><a href="/pkg/runtime/">runtime</a></dt> - <dd> - <p><!-- CL 200081 --> - <code>runtime.Goexit</code> can no longer be aborted by a - recursive <code>panic</code>/<code>recover</code>. - </p> - - <p><!-- CL 188297, CL 191785 --> - On macOS, <code>SIGPIPE</code> is no longer forwarded to signal - handlers installed before the Go runtime is initialized. - This is necessary because macOS delivers <code>SIGPIPE</code> - <a href="https://golang.org/issue/33384">to the main thread</a> - rather than the thread writing to the closed pipe. - </p> - </dd> -</dl><!-- runtime --> - -<dl id="runtime/pprof"><dt><a href="/pkg/runtime/pprof/">runtime/pprof</a></dt> - <dd> - <p><!-- CL 204636, 205097 --> - The generated profile no longer includes the pseudo-PCs used for inline - marks. Symbol information of inlined functions is encoded in - <a href="https://github.com/google/pprof/blob/5e96527/proto/profile.proto#L177-L184">the format</a> - the pprof tool expects. This is a fix for the regression introduced - during recent releases. - </p> - </dd> -</dl><!-- runtime/pprof --> - -<dl id="strconv"><dt><a href="/pkg/strconv/">strconv</a></dt> - <dd> - <p> - The <a href="/pkg/strconv/#NumError"><code>NumError</code></a> - type now has - an <a href="/pkg/strconv/#NumError.Unwrap"><code>Unwrap</code></a> - method that may be used to retrieve the reason that a conversion - failed. - This supports using <code>NumError</code> values - with <a href="/pkg/errors/#Is"><code>errors.Is</code></a> to see - if the underlying error - is <a href="/pkg/strconv/#pkg-variables"><code>strconv.ErrRange</code></a> - or <a href="/pkg/strconv/#pkg-variables"><code>strconv.ErrSyntax</code></a>. - </p> - </dd> -</dl><!-- strconv --> - -<dl id="sync"><dt><a href="/pkg/sync/">sync</a></dt> - <dd> - <p><!-- CL 200577 --> - Unlocking a highly contended <code>Mutex</code> now directly - yields the CPU to the next goroutine waiting for - that <code>Mutex</code>. This significantly improves the - performance of highly contended mutexes on high CPU count - machines. - </p> - </dd> -</dl><!-- sync --> - -<dl id="testing"><dt><a href="/pkg/testing/">testing</a></dt> - <dd> - <p><!-- CL 201359 --> - The testing package now supports cleanup functions, called after - a test or benchmark has finished, by calling - <a href="/pkg/testing#T.Cleanup"><code>T.Cleanup</code></a> or - <a href="/pkg/testing#B.Cleanup"><code>B.Cleanup</code></a> respectively. - </p> - </dd> -</dl><!-- testing --> - -<dl id="text/template"><dt><a href="/pkg/text/template/">text/template</a></dt> - <dd> - <p><!-- CL 206124 --> - The text/template package now correctly reports errors when a - parenthesized argument is used as a function. - This most commonly shows up in erroneous cases like - <code>{{if (eq .F "a") or (eq .F "b")}}</code>. - This should be written as <code>{{if or (eq .F "a") (eq .F "b")}}</code>. - The erroneous case never worked as expected, and will now be - reported with an error <code>can't give argument to non-function</code>. - </p> - </dd> -</dl><!-- text/template --> - -<dl id="unicode"><dt><a href="/pkg/unicode/">unicode</a></dt> - <dd> - <p> - The <a href="/pkg/unicode/"><code>unicode</code></a> package and associated - support throughout the system has been upgraded from Unicode 11.0 to - <a href="https://www.unicode.org/versions/Unicode12.0.0/">Unicode 12.0</a>, - which adds 554 new characters, including four new scripts, and 61 new emoji. - </p> - </dd> -</dl><!-- unicode --> |