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diff --git a/doc/go1.15.html b/doc/go1.15.html deleted file mode 100644 index c9997c0ca3..0000000000 --- a/doc/go1.15.html +++ /dev/null @@ -1,1064 +0,0 @@ -<!--{ - "Title": "Go 1.15 Release Notes", - "Path": "/doc/go1.15" -}--> - -<!-- -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 1.15</h2> - -<p> - The latest Go release, version 1.15, arrives six months after <a href="go1.14">Go 1.14</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> - Go 1.15 includes <a href="#linker">substantial improvements to the linker</a>, - improves <a href="#runtime">allocation for small objects at high core counts</a>, and - deprecates <a href="#commonname">X.509 CommonName</a>. - <code>GOPROXY</code> now supports skipping proxies that return errors and - a new <a href="#time/tzdata">embedded tzdata package</a> has been added. -</p> - -<h2 id="language">Changes to the language</h2> - -<p> - There are no changes to the language. -</p> - -<h2 id="ports">Ports</h2> - -<h3 id="darwin">Darwin</h3> - -<p> - As <a href="go1.14#darwin">announced</a> in the Go 1.14 release - notes, Go 1.15 requires macOS 10.12 Sierra or later; support for - previous versions has been discontinued. -</p> - -<p> <!-- golang.org/issue/37610, golang.org/issue/37611, CL 227582, and CL 227198 --> - As <a href="/doc/go1.14#darwin">announced</a> in the Go 1.14 release - notes, Go 1.15 drops support for 32-bit binaries on macOS, iOS, - iPadOS, watchOS, and tvOS (the <code>darwin/386</code> - and <code>darwin/arm</code> ports). Go continues to support the - 64-bit <code>darwin/amd64</code> and <code>darwin/arm64</code> ports. -</p> - -<h3 id="windows">Windows</h3> - -<p> <!-- CL 214397 and CL 230217 --> - Go now generates Windows ASLR executables when <code>-buildmode=pie</code> - cmd/link flag is provided. Go command uses <code>-buildmode=pie</code> - by default on Windows. -</p> - -<p><!-- CL 227003 --> - The <code>-race</code> and <code>-msan</code> flags now always - enable <code>-d=checkptr</code>, which checks uses - of <code>unsafe.Pointer</code>. This was previously the case on all - OSes except Windows. -</p> - -<p><!-- CL 211139 --> - Go-built DLLs no longer cause the process to exit when it receives a - signal (such as Ctrl-C at a terminal). -</p> - -<h3 id="android">Android</h3> - -<p> <!-- CL 235017, golang.org/issue/38838 --> - When linking binaries for Android, Go 1.15 explicitly selects - the <code>lld</code> linker available in recent versions of the NDK. - The <code>lld</code> linker avoids crashes on some devices, and is - planned to become the default NDK linker in a future NDK version. -</p> - -<h3 id="openbsd">OpenBSD</h3> - -<p><!-- CL 234381 --> - Go 1.15 adds support for OpenBSD 6.7 on <code>GOARCH=arm</code> - and <code>GOARCH=arm64</code>. Previous versions of Go already - supported OpenBSD 6.7 on <code>GOARCH=386</code> - and <code>GOARCH=amd64</code>. -</p> - -<h3 id="riscv">RISC-V</h3> - -<p> <!-- CL 226400, CL 226206, and others --> - There has been progress in improving the stability and performance - of the 64-bit RISC-V port on Linux (<code>GOOS=linux</code>, - <code>GOARCH=riscv64</code>). It also now supports asynchronous - preemption. -</p> - -<h3 id="386">386</h3> - -<p><!-- golang.org/issue/40255 --> - Go 1.15 is the last release to support x87-only floating-point - hardware (<code>GO386=387</code>). Future releases will require at - least SSE2 support on 386, raising Go's - minimum <code>GOARCH=386</code> requirement to the Intel Pentium 4 - (released in 2000) or AMD Opteron/Athlon 64 (released in 2003). -</p> - -<h2 id="tools">Tools</h2> - -<h3 id="go-command">Go command</h3> - -<p><!-- golang.org/issue/37367 --> - The <code>GOPROXY</code> environment variable now supports skipping proxies - that return errors. Proxy URLs may now be separated with either commas - (<code>,</code>) or pipe characters (<code>|</code>). If a proxy URL is - followed by a comma, the <code>go</code> command will only try the next proxy - in the list after a 404 or 410 HTTP response. If a proxy URL is followed by a - pipe character, the <code>go</code> command will try the next proxy in the - list after any error. Note that the default value of <code>GOPROXY</code> - remains <code>https://proxy.golang.org,direct</code>, which does not fall - back to <code>direct</code> in case of errors. -</p> - -<h4 id="go-test"><code>go</code> <code>test</code></h4> - -<p><!-- https://golang.org/issue/36134 --> - Changing the <code>-timeout</code> flag now invalidates cached test results. A - cached result for a test run with a long timeout will no longer count as - passing when <code>go</code> <code>test</code> is re-invoked with a short one. -</p> - -<h4 id="go-flag-parsing">Flag parsing</h4> - -<p><!-- https://golang.org/cl/211358 --> - Various flag parsing issues in <code>go</code> <code>test</code> and - <code>go</code> <code>vet</code> have been fixed. Notably, flags specified - in <code>GOFLAGS</code> are handled more consistently, and - the <code>-outputdir</code> flag now interprets relative paths relative to the - working directory of the <code>go</code> command (rather than the working - directory of each individual test). -</p> - -<h4 id="module-cache">Module cache</h4> - -<p><!-- https://golang.org/cl/219538 --> - The location of the module cache may now be set with - the <code>GOMODCACHE</code> environment variable. The default value of - <code>GOMODCACHE</code> is <code>GOPATH[0]/pkg/mod</code>, the location of the - module cache before this change. -</p> - -<p><!-- https://golang.org/cl/221157 --> - A workaround is now available for Windows "Access is denied" errors in - <code>go</code> commands that access the module cache, caused by external - programs concurrently scanning the file system (see - <a href="https://golang.org/issue/36568">issue #36568</a>). The workaround is - not enabled by default because it is not safe to use when Go versions lower - than 1.14.2 and 1.13.10 are running concurrently with the same module cache. - It can be enabled by explicitly setting the environment variable - <code>GODEBUG=modcacheunzipinplace=1</code>. -</p> - -<h3 id="vet">Vet</h3> - -<h4 id="vet-string-int">New warning for string(x)</h4> - -<p><!-- CL 212919, 232660 --> - The vet tool now warns about conversions of the - form <code>string(x)</code> where <code>x</code> has an integer type - other than <code>rune</code> or <code>byte</code>. - Experience with Go has shown that many conversions of this form - erroneously assume that <code>string(x)</code> evaluates to the - string representation of the integer <code>x</code>. - It actually evaluates to a string containing the UTF-8 encoding of - the value of <code>x</code>. - For example, <code>string(9786)</code> does not evaluate to the - string <code>"9786"</code>; it evaluates to the - string <code>"\xe2\x98\xba"</code>, or <code>"☺"</code>. -</p> - -<p> - Code that is using <code>string(x)</code> correctly can be rewritten - to <code>string(rune(x))</code>. - Or, in some cases, calling <code>utf8.EncodeRune(buf, x)</code> with - a suitable byte slice <code>buf</code> may be the right solution. - Other code should most likely use <code>strconv.Itoa</code> - or <code>fmt.Sprint</code>. -</p> - -<p> - This new vet check is enabled by default when - using <code>go</code> <code>test</code>. -</p> - -<p> - We are considering prohibiting the conversion in a future release of Go. - That is, the language would change to only - permit <code>string(x)</code> for integer <code>x</code> when the - type of <code>x</code> is <code>rune</code> or <code>byte</code>. - Such a language change would not be backward compatible. - We are using this vet check as a first trial step toward changing - the language. -</p> - -<h4 id="vet-impossible-interface">New warning for impossible interface conversions</h4> - -<p><!-- CL 218779, 232660 --> - The vet tool now warns about type assertions from one interface type - to another interface type when the type assertion will always fail. - This will happen if both interface types implement a method with the - same name but with a different type signature. -</p> - -<p> - There is no reason to write a type assertion that always fails, so - any code that triggers this vet check should be rewritten. -</p> - -<p> - This new vet check is enabled by default when - using <code>go</code> <code>test</code>. -</p> - -<p> - We are considering prohibiting impossible interface type assertions - in a future release of Go. - Such a language change would not be backward compatible. - We are using this vet check as a first trial step toward changing - the language. -</p> - -<h2 id="runtime">Runtime</h2> - -<p><!-- CL 221779 --> - If <code>panic</code> is invoked with a value whose type is derived from any - of: <code>bool</code>, <code>complex64</code>, <code>complex128</code>, <code>float32</code>, <code>float64</code>, - <code>int</code>, <code>int8</code>, <code>int16</code>, <code>int32</code>, <code>int64</code>, <code>string</code>, - <code>uint</code>, <code>uint8</code>, <code>uint16</code>, <code>uint32</code>, <code>uint64</code>, <code>uintptr</code>, - then the value will be printed, instead of just its address. - Previously, this was only true for values of exactly these types. -</p> - -<p><!-- CL 228900 --> - On a Unix system, if the <code>kill</code> command - or <code>kill</code> system call is used to send - a <code>SIGSEGV</code>, <code>SIGBUS</code>, - or <code>SIGFPE</code> signal to a Go program, and if the signal - is not being handled via - <a href="/pkg/os/signal/#Notify"><code>os/signal.Notify</code></a>, - the Go program will now reliably crash with a stack trace. - In earlier releases the behavior was unpredictable. -</p> - -<p><!-- CL 221182, CL 229998 --> - Allocation of small objects now performs much better at high core - counts, and has lower worst-case latency. -</p> - -<p><!-- CL 216401 --> - Converting a small integer value into an interface value no longer - causes allocation. -</p> - -<p><!-- CL 216818 --> - Non-blocking receives on closed channels now perform as well as - non-blocking receives on open channels. -</p> - -<h2 id="compiler">Compiler</h2> - -<p><!-- CL 229578 --> - Package <code>unsafe</code>'s <a href="/pkg/unsafe/#Pointer">safety - rules</a> allow converting an <code>unsafe.Pointer</code> - into <code>uintptr</code> when calling certain - functions. Previously, in some cases, the compiler allowed multiple - chained conversions (for example, <code>syscall.Syscall(…,</code> - <code>uintptr(uintptr(ptr)),</code> <code>…)</code>). The compiler - now requires exactly one conversion. Code that used multiple - conversions should be updated to satisfy the safety rules. -</p> - -<p><!-- CL 230544, CL 231397 --> - Go 1.15 reduces typical binary sizes by around 5% compared to Go - 1.14 by eliminating certain types of GC metadata and more - aggressively eliminating unused type metadata. -</p> - -<p><!-- CL 219357, CL 231600 --> - The toolchain now mitigates - <a href="https://www.intel.com/content/www/us/en/support/articles/000055650/processors.html">Intel - CPU erratum SKX102</a> on <code>GOARCH=amd64</code> by aligning - functions to 32 byte boundaries and padding jump instructions. While - this padding increases binary sizes, this is more than made up for - by the binary size improvements mentioned above. -</p> - -<p><!-- CL 222661 --> - Go 1.15 adds a <code>-spectre</code> flag to both the - compiler and the assembler, to allow enabling Spectre mitigations. - These should almost never be needed and are provided mainly as a - “defense in depth” mechanism. - See the <a href="https://github.com/golang/go/wiki/Spectre">Spectre wiki page</a> for details. -</p> - -<p><!-- CL 228578 --> - The compiler now rejects <code>//go:</code> compiler directives that - have no meaning for the declaration they are applied to with a - "misplaced compiler directive" error. Such misapplied directives - were broken before, but were silently ignored by the compiler. -</p> - -<p><!-- CL 206658, CL 205066 --> - The compiler's <code>-json</code> optimization logging now reports - large (>= 128 byte) copies and includes explanations of escape - analysis decisions. -</p> - -<h2 id="linker">Linker</h2> - -<p> - This release includes substantial improvements to the Go linker, - which reduce linker resource usage (both time and memory) and - improve code robustness/maintainability. -</p> - -<p> - For a representative set of large Go programs, linking is 20% faster - and requires 30% less memory on average, for <code>ELF</code>-based - OSes (Linux, FreeBSD, NetBSD, OpenBSD, Dragonfly, and Solaris) - running on <code>amd64</code> architectures, with more modest - improvements for other architecture/OS combinations. -</p> - -<p> - The key contributors to better linker performance are a newly - redesigned object file format, and a revamping of internal - phases to increase concurrency (for example, applying relocations to - symbols in parallel). Object files in Go 1.15 are slightly larger - than their 1.14 equivalents. -</p> - -<p> - These changes are part of a multi-release project - to <a href="https://golang.org/s/better-linker">modernize the Go - linker</a>, meaning that there will be additional linker - improvements expected in future releases. -</p> - -<p><!-- CL 207877 --> - The linker now defaults to internal linking mode - for <code>-buildmode=pie</code> on - <code>linux/amd64</code> and <code>linux/arm64</code>, so these - configurations no longer require a C linker. External linking - mode (which was the default in Go 1.14 for - <code>-buildmode=pie</code>) can still be requested with - <code>-ldflags=-linkmode=external</code> flag. -</p> - -<h2 id="objdump">Objdump</h2> - -<p><!-- CL 225459 --> - The <a href="/cmd/objdump/">objdump</a> tool now supports - disassembling in GNU assembler syntax with the <code>-gnu</code> - flag. -</p> - -<h2 id="library">Core library</h2> - -<h3 id="time/tzdata">New embedded tzdata package</h3> - -<p> <!-- CL 224588 --> - Go 1.15 includes a new package, - <a href="/pkg/time/tzdata/"><code>time/tzdata</code></a>, - that permits embedding the timezone database into a program. - Importing this package (as <code>import _ "time/tzdata"</code>) - permits the program to find timezone information even if the - timezone database is not available on the local system. - You can also embed the timezone database by building - with <code>-tags timetzdata</code>. - Either approach increases the size of the program by about 800 KB. -</p> - -<h3 id="cgo">Cgo</h3> - -<p><!-- CL 235817 --> - Go 1.15 will translate the C type <code>EGLConfig</code> to the - Go type <code>uintptr</code>. This change is similar to how Go - 1.12 and newer treats <code>EGLDisplay</code>, Darwin's CoreFoundation and - Java's JNI types. See the <a href="/cmd/cgo/#hdr-Special_cases">cgo - documentation</a> for more information. -</p> - -<p><!-- CL 250940 --> - In Go 1.15.3 and later, cgo will not permit Go code to allocate an - undefined struct type (a C struct defined as just <code>struct - S;</code> or similar) on the stack or heap. - Go code will only be permitted to use pointers to those types. - Allocating an instance of such a struct and passing a pointer, or a - full struct value, to C code was always unsafe and unlikely to work - correctly; it is now forbidden. - The fix is to either rewrite the Go code to use only pointers, or to - ensure that the Go code sees the full definition of the struct by - including the appropriate C header file. -</p> - -<h3 id="commonname">X.509 CommonName deprecation</h3> - -<p><!-- CL 231379 --> - The deprecated, legacy behavior of treating the <code>CommonName</code> - field on X.509 certificates as a host name when no Subject Alternative Names - are present is now disabled by default. It can be temporarily re-enabled by - adding the value <code>x509ignoreCN=0</code> to the <code>GODEBUG</code> - environment variable. -</p> - -<p> - Note that if the <code>CommonName</code> is an invalid host name, it's always - ignored, regardless of <code>GODEBUG</code> settings. Invalid names include - those with any characters other than letters, digits, hyphens and underscores, - and those with empty labels or trailing dots. -</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="bufio"><dt><a href="/pkg/bufio/">bufio</a></dt> - <dd> - <p><!-- CL 225357, CL 225557 --> - When a <a href="/pkg/bufio/#Scanner"><code>Scanner</code></a> is - used with an invalid - <a href="/pkg/io/#Reader"><code>io.Reader</code></a> that - incorrectly returns a negative number from <code>Read</code>, - the <code>Scanner</code> will no longer panic, but will instead - return the new error - <a href="/pkg/bufio/#ErrBadReadCount"><code>ErrBadReadCount</code></a>. - </p> - </dd> -</dl><!-- bufio --> - -<dl id="context"><dt><a href="/pkg/context/">context</a></dt> - <dd> - <p><!-- CL 223777 --> - Creating a derived <code>Context</code> using a nil parent is now explicitly - disallowed. Any attempt to do so with the - <a href="/pkg/context/#WithValue"><code>WithValue</code></a>, - <a href="/pkg/context/#WithDeadline"><code>WithDeadline</code></a>, or - <a href="/pkg/context/#WithCancel"><code>WithCancel</code></a> functions - will cause a panic. - </p> - </dd> -</dl><!-- context --> - -<dl id="crypto"><dt><a href="/pkg/crypto/">crypto</a></dt> - <dd> - <p><!-- CL 231417, CL 225460 --> - The <code>PrivateKey</code> and <code>PublicKey</code> types in the - <a href="/pkg/crypto/rsa/"><code>crypto/rsa</code></a>, - <a href="/pkg/crypto/ecdsa/"><code>crypto/ecdsa</code></a>, and - <a href="/pkg/crypto/ed25519/"><code>crypto/ed25519</code></a> packages - now have an <code>Equal</code> method to compare keys for equivalence - or to make type-safe interfaces for public keys. The method signature - is compatible with - <a href="https://pkg.go.dev/github.com/google/go-cmp/cmp#Equal"><code>go-cmp</code>'s - definition of equality</a>. - </p> - - <p><!-- CL 224937 --> - <a href="/pkg/crypto/#Hash"><code>Hash</code></a> now implements - <a href="/pkg/fmt/#Stringer"><code>fmt.Stringer</code></a>. - </p> - </dd> -</dl><!-- crypto --> - -<dl id="crypto/ecdsa"><dt><a href="/pkg/crypto/ecdsa/">crypto/ecdsa</a></dt> - <dd> - <p><!-- CL 217940 --> - The new <a href="/pkg/crypto/ecdsa/#SignASN1"><code>SignASN1</code></a> - and <a href="/pkg/crypto/ecdsa/#VerifyASN1"><code>VerifyASN1</code></a> - functions allow generating and verifying ECDSA signatures in the standard - ASN.1 DER encoding. - </p> - </dd> -</dl><!-- crypto/ecdsa --> - -<dl id="crypto/elliptic"><dt><a href="/pkg/crypto/elliptic/">crypto/elliptic</a></dt> - <dd> - <p><!-- CL 202819 --> - The new <a href="/pkg/crypto/elliptic/#MarshalCompressed"><code>MarshalCompressed</code></a> - and <a href="/pkg/crypto/elliptic/#UnmarshalCompressed"><code>UnmarshalCompressed</code></a> - functions allow encoding and decoding NIST elliptic curve points in compressed format. - </p> - </dd> -</dl><!-- crypto/elliptic --> - -<dl id="crypto/rsa"><dt><a href="/pkg/crypto/rsa/">crypto/rsa</a></dt> - <dd> - <p><!-- CL 226203 --> - <a href="/pkg/crypto/rsa/#VerifyPKCS1v15"><code>VerifyPKCS1v15</code></a> - now rejects invalid short signatures with missing leading zeroes, according to RFC 8017. - </p> - </dd> -</dl><!-- crypto/rsa --> - -<dl id="crypto/tls"><dt><a href="/pkg/crypto/tls/">crypto/tls</a></dt> - <dd> - <p><!-- CL 214977 --> - The new - <a href="/pkg/crypto/tls/#Dialer"><code>Dialer</code></a> - type and its - <a href="/pkg/crypto/tls/#Dialer.DialContext"><code>DialContext</code></a> - method permit using a context to both connect and handshake with a TLS server. - </p> - - <p><!-- CL 229122 --> - The new - <a href="/pkg/crypto/tls/#Config.VerifyConnection"><code>VerifyConnection</code></a> - callback on the <a href="/pkg/crypto/tls/#Config"><code>Config</code></a> type - allows custom verification logic for every connection. It has access to the - <a href="/pkg/crypto/tls/#ConnectionState"><code>ConnectionState</code></a> - which includes peer certificates, SCTs, and stapled OCSP responses. - </p> - - <p><!-- CL 230679 --> - Auto-generated session ticket keys are now automatically rotated every 24 hours, - with a lifetime of 7 days, to limit their impact on forward secrecy. - </p> - - <p><!-- CL 231317 --> - Session ticket lifetimes in TLS 1.2 and earlier, where the session keys - are reused for resumed connections, are now limited to 7 days, also to - limit their impact on forward secrecy. - </p> - - <p><!-- CL 231038 --> - The client-side downgrade protection checks specified in RFC 8446 are now - enforced. This has the potential to cause connection errors for clients - encountering middleboxes that behave like unauthorized downgrade attacks. - </p> - - <p><!-- CL 208226 --> - <a href="/pkg/crypto/tls/#SignatureScheme"><code>SignatureScheme</code></a>, - <a href="/pkg/crypto/tls/#CurveID"><code>CurveID</code></a>, and - <a href="/pkg/crypto/tls/#ClientAuthType"><code>ClientAuthType</code></a> - now implement <a href="/pkg/fmt/#Stringer"><code>fmt.Stringer</code></a>. - </p> - - <p><!-- CL 236737 --> - The <a href="/pkg/crypto/tls/#ConnectionState"><code>ConnectionState</code></a> - fields <code>OCSPResponse</code> and <code>SignedCertificateTimestamps</code> - are now repopulated on client-side resumed connections. - </p> - - <p><!-- CL 227840 --> - <a href="/pkg/crypto/tls/#Conn"><code>tls.Conn</code></a> - now returns an opaque error on permanently broken connections, wrapping - the temporary - <a href="/pkg/net/http/#Error"><code>net.Error</code></a>. To access the - original <code>net.Error</code>, use - <a href="/pkg/errors/#As"><code>errors.As</code></a> (or - <a href="/pkg/errors/#Unwrap"><code>errors.Unwrap</code></a>) instead of a - type assertion. - </p> - </dd> -</dl><!-- crypto/tls --> - -<dl id="crypto/x509"><dt><a href="/pkg/crypto/x509/">crypto/x509</a></dt> - <dd> - <p><!-- CL 231378, CL 231380, CL 231381 --> - If either the name on the certificate or the name being verified (with - <a href="/pkg/crypto/x509/#VerifyOptions.DNSName"><code>VerifyOptions.DNSName</code></a> - or <a href="/pkg/crypto/x509/#Certificate.VerifyHostname"><code>VerifyHostname</code></a>) - are invalid, they will now be compared case-insensitively without further - processing (without honoring wildcards or stripping trailing dots). - Invalid names include those with any characters other than letters, - digits, hyphens and underscores, those with empty labels, and names on - certificates with trailing dots. - </p> - - <p><!-- CL 217298 --> - The new <a href="/pkg/crypto/x509/#CreateRevocationList"><code>CreateRevocationList</code></a> - function and <a href="/pkg/crypto/x509/#RevocationList"><code>RevocationList</code></a> type - allow creating RFC 5280-compliant X.509 v2 Certificate Revocation Lists. - </p> - - <p><!-- CL 227098 --> - <a href="/pkg/crypto/x509/#CreateCertificate"><code>CreateCertificate</code></a> - now automatically generates the <code>SubjectKeyId</code> if the template - is a CA and doesn't explicitly specify one. - </p> - - <p><!-- CL 228777 --> - <a href="/pkg/crypto/x509/#CreateCertificate"><code>CreateCertificate</code></a> - now returns an error if the template specifies <code>MaxPathLen</code> but is not a CA. - </p> - - <p><!-- CL 205237 --> - On Unix systems other than macOS, the <code>SSL_CERT_DIR</code> - environment variable can now be a colon-separated list. - </p> - - <p><!-- CL 227037 --> - On macOS, binaries are now always linked against - <code>Security.framework</code> to extract the system trust roots, - regardless of whether cgo is available. The resulting behavior should be - more consistent with the OS verifier. - </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 229864, CL 240543 --> - <a href="/pkg/crypto/x509/pkix/#Name.String"><code>Name.String</code></a> - now prints non-standard attributes from - <a href="/pkg/crypto/x509/pkix/#Name.Names"><code>Names</code></a> if - <a href="/pkg/crypto/x509/pkix/#Name.ExtraNames"><code>ExtraNames</code></a> is nil. - </p> - </dd> -</dl><!-- crypto/x509/pkix --> - -<dl id="database/sql"><dt><a href="/pkg/database/sql/">database/sql</a></dt> - <dd> - <p><!-- CL 145758 --> - The new <a href="/pkg/database/sql/#DB.SetConnMaxIdleTime"><code>DB.SetConnMaxIdleTime</code></a> - method allows removing a connection from the connection pool after - it has been idle for a period of time, without regard to the total - lifespan of the connection. The <a href="/pkg/database/sql/#DBStats.MaxIdleTimeClosed"><code>DBStats.MaxIdleTimeClosed</code></a> - field shows the total number of connections closed due to - <code>DB.SetConnMaxIdleTime</code>. - </p> - - <p><!-- CL 214317 --> - The new <a href="/pkg/database/sql/#Row.Err"><code>Row.Err</code></a> getter - allows checking for query errors without calling - <code>Row.Scan</code>. - </p> - </dd> -</dl><!-- database/sql --> - -<dl id="database/sql/driver"><dt><a href="/pkg/database/sql/driver/">database/sql/driver</a></dt> - <dd> - <p><!-- CL 174122 --> - The new <a href="/pkg/database/sql/driver/#Validator"><code>Validator</code></a> - interface may be implemented by <code>Conn</code> to allow drivers - to signal if a connection is valid or if it should be discarded. - </p> - </dd> -</dl><!-- database/sql/driver --> - -<dl id="debug/pe"><dt><a href="/pkg/debug/pe/">debug/pe</a></dt> - <dd> - <p><!-- CL 222637 --> - The package now defines the - <code>IMAGE_FILE</code>, <code>IMAGE_SUBSYSTEM</code>, - and <code>IMAGE_DLLCHARACTERISTICS</code> constants used by the - PE file format. - </p> - </dd> -</dl><!-- debug/pe --> - -<dl id="encoding/asn1"><dt><a href="/pkg/encoding/asn1/">encoding/asn1</a></dt> - <dd> - <p><!-- CL 226984 --> - <a href="/pkg/encoding/asn1/#Marshal"><code>Marshal</code></a> now sorts the components - of SET OF according to X.690 DER. - </p> - - <p><!-- CL 227320 --> - <a href="/pkg/encoding/asn1/#Unmarshal"><code>Unmarshal</code></a> now rejects tags and - Object Identifiers which are not minimally encoded according to X.690 DER. - </p> - </dd> -</dl><!-- encoding/asn1 --> - -<dl id="encoding/json"><dt><a href="/pkg/encoding/json/">encoding/json</a></dt> - <dd> - <p><!-- CL 199837 --> - The package now has an internal limit to the maximum depth of - nesting when decoding. This reduces the possibility that a - deeply nested input could use large quantities of stack memory, - or even cause a "goroutine stack exceeds limit" panic. - </p> - </dd> -</dl><!-- encoding/json --> - -<dl id="flag"><dt><a href="/pkg/flag/">flag</a></dt> - <dd> - <p><!-- CL 221427 --> - When the <code>flag</code> package sees <code>-h</code> or <code>-help</code>, - and those flags are not defined, it now prints a usage message. - If the <a href="/pkg/flag/#FlagSet"><code>FlagSet</code></a> was created with - <a href="/pkg/flag/#ExitOnError"><code>ExitOnError</code></a>, - <a href="/pkg/flag/#FlagSet.Parse"><code>FlagSet.Parse</code></a> would then - exit with a status of 2. In this release, the exit status for <code>-h</code> - or <code>-help</code> has been changed to 0. In particular, this applies to - the default handling of command line flags. - </p> - </dd> -</dl> - -<dl id="fmt"><dt><a href="/pkg/fmt/">fmt</a></dt> - <dd> - <p><!-- CL 215001 --> - The printing verbs <code>%#g</code> and <code>%#G</code> now preserve - trailing zeros for floating-point values. - </p> - </dd> -</dl><!-- fmt --> - -<dl id="go/format"><dt><a href="/pkg/go/format/">go/format</a></dt> - <dd> - <p><!-- golang.org/issue/37476, CL 231461, CL 240683 --> - The <a href="/pkg/go/format/#Source"><code>Source</code></a> and - <a href="/pkg/go/format/#Node"><code>Node</code></a> functions - now canonicalize number literal prefixes and exponents as part - of formatting Go source code. This matches the behavior of the - <a href="/pkg/cmd/gofmt/"><code>gofmt</code></a> command as it - was implemented <a href="/doc/go1.13#gofmt">since Go 1.13</a>. - </p> - </dd> -</dl><!-- go/format --> - -<dl id="html/template"><dt><a href="/pkg/html/template/">html/template</a></dt> - <dd> - <p><!-- CL 226097 --> - The package now uses Unicode escapes (<code>\uNNNN</code>) in all - JavaScript and JSON contexts. This fixes escaping errors in - <code>application/ld+json</code> and <code>application/json</code> - contexts. - </p> - </dd> -</dl><!-- html/template --> - -<dl id="io/ioutil"><dt><a href="/pkg/io/ioutil/">io/ioutil</a></dt> - <dd> - <p><!-- CL 212597 --> - <a href="/pkg/io/ioutil/#TempDir"><code>TempDir</code></a> and - <a href="/pkg/io/ioutil/#TempFile"><code>TempFile</code></a> - now reject patterns that contain path separators. - That is, calls such as <code>ioutil.TempFile("/tmp",</code> <code>"../base*")</code> will no longer succeed. - This prevents unintended directory traversal. - </p> - </dd> -</dl><!-- io/ioutil --> - -<dl id="math/big"><dt><a href="/pkg/math/big/">math/big</a></dt> - <dd> - <p><!-- CL 230397 --> - The new <a href="/pkg/math/big/#Int.FillBytes"><code>Int.FillBytes</code></a> - method allows serializing to fixed-size pre-allocated byte slices. - </p> - </dd> -</dl><!-- math/big --> - -<dl id="math/cmplx"><dt><a href="/pkg/math/cmplx/">math/cmplx</a></dt> - <dd> - <p><!-- CL 220689 --> - The functions in this package were updated to conform to the C99 standard - (Annex G IEC 60559-compatible complex arithmetic) with respect to handling - of special arguments such as infinity, NaN and signed zero. - </p> - </dd> -</dl><!-- math/cmplx--> - -<dl id="net"><dt><a href="/pkg/net/">net</a></dt> - <dd> - <p><!-- CL 228645 --> - If an I/O operation exceeds a deadline set by - the <a href="/pkg/net/#Conn"><code>Conn.SetDeadline</code></a>, - <code>Conn.SetReadDeadline</code>, - or <code>Conn.SetWriteDeadline</code> methods, it will now - return an error that is or wraps - <a href="/pkg/os/#ErrDeadlineExceeded"><code>os.ErrDeadlineExceeded</code></a>. - This may be used to reliably detect whether an error is due to - an exceeded deadline. - Earlier releases recommended calling the <code>Timeout</code> - method on the error, but I/O operations can return errors for - which <code>Timeout</code> returns <code>true</code> although a - deadline has not been exceeded. - </p> - - <p><!-- CL 228641 --> - The new <a href="/pkg/net/#Resolver.LookupIP"><code>Resolver.LookupIP</code></a> - method supports IP lookups that are both network-specific and accept a context. - </p> - </dd> -</dl> - -<dl id="net/http"><dt><a href="/pkg/net/http/">net/http</a></dt> - <dd> - <p><!-- CL 231418, CL 231419 --> - Parsing is now stricter as a hardening measure against request smuggling attacks: - non-ASCII white space is no longer trimmed like SP and HTAB, and support for the - "<code>identity</code>" <code>Transfer-Encoding</code> was dropped. - </p> - </dd> -</dl><!-- net/http --> - -<dl id="net/http/httputil"><dt><a href="/pkg/net/http/httputil/">net/http/httputil</a></dt> - <dd> - <p><!-- CL 230937 --> - <a href="/pkg/net/http/httputil/#ReverseProxy"><code>ReverseProxy</code></a> - now supports not modifying the <code>X-Forwarded-For</code> - header when the incoming <code>Request.Header</code> map entry - for that field is <code>nil</code>. - </p> - - <p><!-- CL 224897 --> - When a Switching Protocol (like WebSocket) request handled by - <a href="/pkg/net/http/httputil/#ReverseProxy"><code>ReverseProxy</code></a> - is canceled, the backend connection is now correctly closed. - </p> - </dd> -</dl> - -<dl id="net/http/pprof"><dt><a href="/pkg/net/http/pprof/">net/http/pprof</a></dt> - <dd> - <p><!-- CL 147598, CL 229537 --> - All profile endpoints now support a "<code>seconds</code>" parameter. When present, - the endpoint profiles for the specified number of seconds and reports the difference. - The meaning of the "<code>seconds</code>" parameter in the <code>cpu</code> profile and - the trace endpoints is unchanged. - </p> - </dd> -</dl> - -<dl id="net/url"><dt><a href="/pkg/net/url/">net/url</a></dt> - <dd> - <p><!-- CL 227645 --> - The new <a href="/pkg/net/url/#URL"><code>URL</code></a> field - <code>RawFragment</code> and method <a href="/pkg/net/url/#URL.EscapedFragment"><code>EscapedFragment</code></a> - provide detail about and control over the exact encoding of a particular fragment. - These are analogous to - <code>RawPath</code> and <a href="/pkg/net/url/#URL.EscapedPath"><code>EscapedPath</code></a>. - </p> - <p><!-- CL 207082 --> - The new <a href="/pkg/net/url/#URL"><code>URL</code></a> - method <a href="/pkg/net/url/#URL.Redacted"><code>Redacted</code></a> - returns the URL in string form with any password replaced with <code>xxxxx</code>. - </p> - </dd> -</dl> - -<dl id="os"><dt><a href="/pkg/os/">os</a></dt> - <dd> - <p><!-- CL --> - If an I/O operation exceeds a deadline set by - the <a href="/pkg/os/#File.SetDeadline"><code>File.SetDeadline</code></a>, - <a href="/pkg/os/#File.SetReadDeadline"><code>File.SetReadDeadline</code></a>, - or <a href="/pkg/os/#File.SetWriteDeadline"><code>File.SetWriteDeadline</code></a> - methods, it will now return an error that is or wraps - <a href="/pkg/os/#ErrDeadlineExceeded"><code>os.ErrDeadlineExceeded</code></a>. - This may be used to reliably detect whether an error is due to - an exceeded deadline. - Earlier releases recommended calling the <code>Timeout</code> - method on the error, but I/O operations can return errors for - which <code>Timeout</code> returns <code>true</code> although a - deadline has not been exceeded. - </p> - - <p><!-- CL 232862 --> - Packages <code>os</code> and <code>net</code> now automatically - retry system calls that fail with <code>EINTR</code>. Previously - this led to spurious failures, which became more common in Go - 1.14 with the addition of asynchronous preemption. Now this is - handled transparently. - </p> - - <p><!-- CL 229101 --> - The <a href="/pkg/os/#File"><code>os.File</code></a> type now - supports a <a href="/pkg/os/#File.ReadFrom"><code>ReadFrom</code></a> - method. This permits the use of the <code>copy_file_range</code> - system call on some systems when using - <a href="/pkg/io/#Copy"><code>io.Copy</code></a> to copy data - from one <code>os.File</code> to another. A consequence is that - <a href="/pkg/io/#CopyBuffer"><code>io.CopyBuffer</code></a> - will not always use the provided buffer when copying to a - <code>os.File</code>. If a program wants to force the use of - the provided buffer, it can be done by writing - <code>io.CopyBuffer(struct{ io.Writer }{dst}, src, buf)</code>. - </p> - </dd> -</dl> - -<dl id="plugin"><dt><a href="/pkg/plugin/">plugin</a></dt> - <dd> - <p><!-- CL 182959 --> - DWARF generation is now supported (and enabled by default) for <code>-buildmode=plugin</code> on macOS. - </p> - </dd> - <dd> - <p><!-- CL 191617 --> - Building with <code>-buildmode=plugin</code> is now supported on <code>freebsd/amd64</code>. - </p> - </dd> -</dl> - -<dl id="reflect"><dt><a href="/pkg/reflect/">reflect</a></dt> - <dd> - <p><!-- CL 228902 --> - Package <code>reflect</code> now disallows accessing methods of all - non-exported fields, whereas previously it allowed accessing - those of non-exported, embedded fields. Code that relies on the - previous behavior should be updated to instead access the - corresponding promoted method of the enclosing variable. - </p> - </dd> -</dl> - -<dl id="regexp"><dt><a href="/pkg/regexp/">regexp</a></dt> - <dd> - <p><!-- CL 187919 --> - The new <a href="/pkg/regexp/#Regexp.SubexpIndex"><code>Regexp.SubexpIndex</code></a> - method returns the index of the first subexpression with the given name - within the regular expression. - </p> - </dd> -</dl><!-- regexp --> - -<dl id="pkg-runtime"><dt><a href="/pkg/runtime/">runtime</a></dt> - <dd> - <p><!-- CL 216557 --> - Several functions, including - <a href="/pkg/runtime/#ReadMemStats"><code>ReadMemStats</code></a> - and - <a href="/pkg/runtime/#GoroutineProfile"><code>GoroutineProfile</code></a>, - no longer block if a garbage collection is in progress. - </p> - </dd> -</dl> - -<dl id="pkg-runtime-pprof"><dt><a href="/pkg/runtime/pprof/">runtime/pprof</a></dt> - <dd> - <p><!-- CL 189318 --> - The goroutine profile now includes the profile labels associated with each - goroutine at the time of profiling. This feature is not yet implemented for - the profile reported with <code>debug=2</code>. - </p> - </dd> -</dl> - -<dl id="strconv"><dt><a href="/pkg/strconv/">strconv</a></dt> - <dd> - <p><!-- CL 216617 --> - <a href="/pkg/strconv/#FormatComplex"><code>FormatComplex</code></a> and <a href="/pkg/strconv/#ParseComplex"><code>ParseComplex</code></a> are added for working with complex numbers. - </p> - <p> - <a href="/pkg/strconv/#FormatComplex"><code>FormatComplex</code></a> converts a complex number into a string of the form (a+bi), where a and b are the real and imaginary parts. - </p> - <p> - <a href="/pkg/strconv/#ParseComplex"><code>ParseComplex</code></a> converts a string into a complex number of a specified precision. <code>ParseComplex</code> accepts complex numbers in the format <code>N+Ni</code>. - </p> - </dd> -</dl><!-- strconv --> - -<dl id="sync"><dt><a href="/pkg/sync/">sync</a></dt> - <dd> - <p><!-- CL 205899, golang.org/issue/33762 --> - The new method - <a href="/pkg/sync/#Map.LoadAndDelete"><code>Map.LoadAndDelete</code></a> - atomically deletes a key and returns the previous value if present. - </p> - <p><!-- CL 205899 --> - The method - <a href="/pkg/sync/#Map.Delete"><code>Map.Delete</code></a> - is more efficient. - </p> - </dd> -</dl><!-- sync --> - -<dl id="syscall"><dt><a href="/pkg/syscall/">syscall</a></dt> - <dd> - <p><!-- CL 231638 --> - On Unix systems, functions that use - <a href="/pkg/syscall/#SysProcAttr"><code>SysProcAttr</code></a> - will now reject attempts to set both the <code>Setctty</code> - and <code>Foreground</code> fields, as they both use - the <code>Ctty</code> field but do so in incompatible ways. - We expect that few existing programs set both fields. - </p> - <p> - Setting the <code>Setctty</code> field now requires that the - <code>Ctty</code> field be set to a file descriptor number in the - child process, as determined by the <code>ProcAttr.Files</code> field. - Using a child descriptor always worked, but there were certain - cases where using a parent file descriptor also happened to work. - Some programs that set <code>Setctty</code> will need to change - the value of <code>Ctty</code> to use a child descriptor number. - </p> - - <p><!-- CL 220578 --> - It is <a href="/pkg/syscall/#Proc.Call">now possible</a> to call - system calls that return floating point values - on <code>windows/amd64</code>. - </p> - </dd> -</dl> - -<dl id="testing"><dt><a href="/pkg/testing/">testing</a></dt> - <dd> - <p><!-- golang.org/issue/28135 --> - The <code>testing.T</code> type now has a - <a href="/pkg/testing/#T.Deadline"><code>Deadline</code></a> method - that reports the time at which the test binary will have exceeded its - timeout. - </p> - - <p><!-- golang.org/issue/34129 --> - A <code>TestMain</code> function is no longer required to call - <code>os.Exit</code>. If a <code>TestMain</code> function returns, - the test binary will call <code>os.Exit</code> with the value returned - by <code>m.Run</code>. - </p> - - <p><!-- CL 226877, golang.org/issue/35998 --> - The new methods - <a href="/pkg/testing/#T.TempDir"><code>T.TempDir</code></a> and - <a href="/pkg/testing/#B.TempDir"><code>B.TempDir</code></a> - return temporary directories that are automatically cleaned up - at the end of the test. - </p> - - <p><!-- CL 229085 --> - <code>go</code> <code>test</code> <code>-v</code> now groups output by - test name, rather than printing the test name on each line. - </p> - </dd> -</dl><!-- testing --> - -<dl id="text/template"><dt><a href="/pkg/text/template/">text/template</a></dt> - <dd> - <p><!-- CL 226097 --> - <a href="/pkg/text/template/#JSEscape"><code>JSEscape</code></a> now - consistently uses Unicode escapes (<code>\u00XX</code>), which are - compatible with JSON. - </p> - </dd> -</dl><!-- text/template --> - -<dl id="time"><dt><a href="/pkg/time/">time</a></dt> - <dd> - <p><!-- CL 220424, CL 217362, golang.org/issue/33184 --> - The new method - <a href="/pkg/time/#Ticker.Reset"><code>Ticker.Reset</code></a> - supports changing the duration of a ticker. - </p> - - <p><!-- CL 227878 --> - When returning an error, <a href="/pkg/time/#ParseDuration"><code>ParseDuration</code></a> now quotes the original value. - </p> - </dd> -</dl><!-- time --> |