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diff --git a/doc/go1.8.html b/doc/go1.8.html deleted file mode 100644 index 2a47fac420..0000000000 --- a/doc/go1.8.html +++ /dev/null @@ -1,1666 +0,0 @@ -<!--{ - "Title": "Go 1.8 Release Notes", - "Path": "/doc/go1.8", - "Template": true -}--> - -<!-- -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 1.8</h2> - -<p> -The latest Go release, version 1.8, arrives six months after <a href="go1.7">Go 1.7</a>. -Most of its changes are in the implementation of the toolchain, runtime, and libraries. -There are <a href="#language">two minor changes</a> to the language specification. -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> -The release <a href="#ports">adds support for 32-bit MIPS</a>, -<a href="#compiler">updates the compiler back end</a> to generate more efficient code, -<a href="#gc">reduces GC pauses</a> by eliminating stop-the-world stack rescanning, -<a href="#h2push">adds HTTP/2 Push support</a>, -<a href="#http_shutdown">adds HTTP graceful shutdown</a>, -<a href="#more_context">adds more context support</a>, -<a href="#mutex_prof">enables profiling mutexes</a>, -and <a href="#sort_slice">simplifies sorting slices</a>. -</p> - -<h2 id="language">Changes to the language</h2> - -<p> - When explicitly converting a value from one struct type to another, - as of Go 1.8 the tags are ignored. Thus two structs that differ - only in their tags may be converted from one to the other: -</p> - -<pre> -func example() { - type T1 struct { - X int `json:"foo"` - } - type T2 struct { - X int `json:"bar"` - } - var v1 T1 - var v2 T2 - v1 = T1(v2) // now legal -} -</pre> - - -<p> <!-- CL 17711 --> - The language specification now only requires that implementations - support up to 16-bit exponents in floating-point constants. This does not affect - either the “<a href="/cmd/compile/"><code>gc</code></a>” or - <code>gccgo</code> compilers, both of - which still support 32-bit exponents. -</p> - -<h2 id="ports">Ports</h2> - -<p> -Go now supports 32-bit MIPS on Linux for both big-endian -(<code>linux/mips</code>) and little-endian machines -(<code>linux/mipsle</code>) that implement the MIPS32r1 instruction set with FPU -or kernel FPU emulation. Note that many common MIPS-based routers lack an FPU and -have firmware that doesn't enable kernel FPU emulation; Go won't run on such machines. -</p> - -<p> -On DragonFly BSD, Go now requires DragonFly 4.4.4 or later. <!-- CL 29491, CL 29971 --> -</p> - -<p> -On OpenBSD, Go now requires OpenBSD 5.9 or later. <!-- CL 34093 --> -</p> - -<p> -The Plan 9 port's networking support is now much more complete -and matches the behavior of Unix and Windows with respect to deadlines -and cancelation. For Plan 9 kernel requirements, see the -<a href="https://golang.org/wiki/Plan9">Plan 9 wiki page</a>. -</p> - -<p> - Go 1.8 now only supports OS X 10.8 or later. This is likely the last - Go release to support 10.8. Compiling Go or running - binaries on older OS X versions is untested. -</p> - -<p> - Go 1.8 will be the last release to support Linux on ARMv5E and ARMv6 processors: - Go 1.9 will likely require the ARMv6K (as found in the Raspberry Pi 1) or later. - To identify whether a Linux system is ARMv6K or later, run - “<code>go</code> <code>tool</code> <code>dist</code> <code>-check-armv6k</code>” - (to facilitate testing, it is also possible to just copy the <code>dist</code> command to the - system without installing a full copy of Go 1.8) - and if the program terminates with output "ARMv6K supported." then the system - implements ARMv6K or later. - Go on non-Linux ARM systems already requires ARMv6K or later. -</p> - - -<h3 id="known_issues">Known Issues</h3> - -<p> -There are some instabilities on FreeBSD and NetBSD that are known but not understood. -These can lead to program crashes in rare cases. -See -<a href="https://golang.org/issue/15658">issue 15658</a> and -<a href="https://golang.org/issue/16511">issue 16511</a>. -Any help in solving these issues would be appreciated. -</p> - -<h2 id="tools">Tools</h2> - -<h3 id="cmd_asm">Assembler</h3> - -<p> -For 64-bit x86 systems, the following instructions have been added: -<code>VBROADCASTSD</code>, -<code>BROADCASTSS</code>, -<code>MOVDDUP</code>, -<code>MOVSHDUP</code>, -<code>MOVSLDUP</code>, -<code>VMOVDDUP</code>, -<code>VMOVSHDUP</code>, and -<code>VMOVSLDUP</code>. -</p> - -<p> -For 64-bit PPC systems, the common vector scalar instructions have been -added: -<code>LXS</code>, -<code>LXSDX</code>, -<code>LXSI</code>, -<code>LXSIWAX</code>, -<code>LXSIWZX</code>, -<code>LXV</code>, -<code>LXVD2X</code>, -<code>LXVDSX</code>, -<code>LXVW4X</code>, -<code>MFVSR</code>, -<code>MFVSRD</code>, -<code>MFVSRWZ</code>, -<code>MTVSR</code>, -<code>MTVSRD</code>, -<code>MTVSRWA</code>, -<code>MTVSRWZ</code>, -<code>STXS</code>, -<code>STXSDX</code>, -<code>STXSI</code>, -<code>STXSIWX</code>, -<code>STXV</code>, -<code>STXVD2X</code>, -<code>STXVW4X</code>, -<code>XSCV</code>, -<code>XSCVDPSP</code>, -<code>XSCVDPSPN</code>, -<code>XSCVDPSXDS</code>, -<code>XSCVDPSXWS</code>, -<code>XSCVDPUXDS</code>, -<code>XSCVDPUXWS</code>, -<code>XSCVSPDP</code>, -<code>XSCVSPDPN</code>, -<code>XSCVSXDDP</code>, -<code>XSCVSXDSP</code>, -<code>XSCVUXDDP</code>, -<code>XSCVUXDSP</code>, -<code>XSCVX</code>, -<code>XSCVXP</code>, -<code>XVCV</code>, -<code>XVCVDPSP</code>, -<code>XVCVDPSXDS</code>, -<code>XVCVDPSXWS</code>, -<code>XVCVDPUXDS</code>, -<code>XVCVDPUXWS</code>, -<code>XVCVSPDP</code>, -<code>XVCVSPSXDS</code>, -<code>XVCVSPSXWS</code>, -<code>XVCVSPUXDS</code>, -<code>XVCVSPUXWS</code>, -<code>XVCVSXDDP</code>, -<code>XVCVSXDSP</code>, -<code>XVCVSXWDP</code>, -<code>XVCVSXWSP</code>, -<code>XVCVUXDDP</code>, -<code>XVCVUXDSP</code>, -<code>XVCVUXWDP</code>, -<code>XVCVUXWSP</code>, -<code>XVCVX</code>, -<code>XVCVXP</code>, -<code>XXLAND</code>, -<code>XXLANDC</code>, -<code>XXLANDQ</code>, -<code>XXLEQV</code>, -<code>XXLNAND</code>, -<code>XXLNOR</code>, -<code>XXLOR</code>, -<code>XXLORC</code>, -<code>XXLORQ</code>, -<code>XXLXOR</code>, -<code>XXMRG</code>, -<code>XXMRGHW</code>, -<code>XXMRGLW</code>, -<code>XXPERM</code>, -<code>XXPERMDI</code>, -<code>XXSEL</code>, -<code>XXSI</code>, -<code>XXSLDWI</code>, -<code>XXSPLT</code>, and -<code>XXSPLTW</code>. -</p> - -<h3 id="tool_yacc">Yacc</h3> - -<p> <!-- CL 27324, CL 27325 --> -The <code>yacc</code> tool (previously available by running -“<code>go</code> <code>tool</code> <code>yacc</code>”) has been removed. -As of Go 1.7 it was no longer used by the Go compiler. -It has moved to the “tools” repository and is now available at -<code><a href="https://godoc.org/golang.org/x/tools/cmd/goyacc">golang.org/x/tools/cmd/goyacc</a></code>. -</p> - -<h3 id="tool_fix">Fix</h3> - -<p> <!-- CL 28872 --> - The <code>fix</code> tool has a new “<code>context</code>” - fix to change imports from “<code>golang.org/x/net/context</code>” - to “<a href="/pkg/context/"><code>context</code></a>”. -</p> - -<h3 id="tool_pprof">Pprof</h3> - -<p> <!-- CL 33157 --> - The <code>pprof</code> tool can now profile TLS servers - and skip certificate validation by using the “<code>https+insecure</code>” - URL scheme. -</p> - -<p> <!-- CL 23781 --> - The callgrind output now has instruction-level granularity. -</p> - -<h3 id="tool_trace">Trace</h3> - -<p> <!-- CL 23324 --> - The <code>trace</code> tool has a new <code>-pprof</code> flag for - producing pprof-compatible blocking and latency profiles from an - execution trace. -</p> - -<p> <!-- CL 30017, CL 30702 --> - Garbage collection events are now shown more clearly in the - execution trace viewer. Garbage collection activity is shown on its - own row and GC helper goroutines are annotated with their roles. -</p> - -<h3 id="tool_vet">Vet</h3> - -<p>Vet is stricter in some ways and looser where it - previously caused false positives.</p> - -<p>Vet now checks for copying an array of locks, - duplicate JSON and XML struct field tags, - non-space-separated struct tags, - deferred calls to HTTP <code>Response.Body.Close</code> - before checking errors, and - indexed arguments in <code>Printf</code>. - It also improves existing checks.</p> -</p> - -<h3 id="compiler">Compiler Toolchain</h3> - -<p> -Go 1.7 introduced a new compiler back end for 64-bit x86 systems. -In Go 1.8, that back end has been developed further and is now used for -all architectures. -</p> - -<p> -The new back end, based on -<a href="https://en.wikipedia.org/wiki/Static_single_assignment_form">static single assignment form</a> (SSA), -generates more compact, more efficient code -and provides a better platform for optimizations -such as bounds check elimination. -The new back end reduces the CPU time required by -<a href="https://golang.org/test/bench/go1/">our benchmark programs</a> by 20-30% -on 32-bit ARM systems. For 64-bit x86 systems, which already used the SSA back end in -Go 1.7, the gains are a more modest 0-10%. Other architectures will likely -see improvements closer to the 32-bit ARM numbers. -</p> - -<p> - The temporary <code>-ssa=0</code> compiler flag introduced in Go 1.7 - to disable the new back end has been removed in Go 1.8. -</p> - -<p> - In addition to enabling the new compiler back end for all systems, - Go 1.8 also introduces a new compiler front end. The new compiler - front end should not be noticeable to users but is the foundation for - future performance work. -</p> - -<p> - The compiler and linker have been optimized and run faster in this - release than in Go 1.7, although they are still slower than we would - like and will continue to be optimized in future releases. - Compared to the previous release, Go 1.8 is - <a href="https://dave.cheney.net/2016/11/19/go-1-8-toolchain-improvements">about 15% faster</a>. -</p> - -<h3 id="cmd_cgo">Cgo</h3> - -<p> <!-- CL 31141 --> -The Go tool now remembers the value of the <code>CGO_ENABLED</code> environment -variable set during <code>make.bash</code> and applies it to all future compilations -by default to fix issue <a href="https://golang.org/issue/12808">#12808</a>. -When doing native compilation, it is rarely necessary to explicitly set -the <code>CGO_ENABLED</code> environment variable as <code>make.bash</code> -will detect the correct setting automatically. The main reason to explicitly -set the <code>CGO_ENABLED</code> environment variable is when your environment -supports cgo, but you explicitly do not want cgo support, in which case, set -<code>CGO_ENABLED=0</code> during <code>make.bash</code> or <code>all.bash</code>. -</p> - -<p> <!-- CL 29991 --> -The environment variable <code>PKG_CONFIG</code> may now be used to -set the program to run to handle <code>#cgo</code> <code>pkg-config</code> -directives. The default is <code>pkg-config</code>, the program -always used by earlier releases. This is intended to make it easier -to cross-compile -<a href="/cmd/cgo/">cgo</a> code. -</p> - -<p> <!-- CL 32354 --> -The <a href="/cmd/cgo/">cgo</a> tool now supports a <code>-srcdir</code> -option, which is used by the <a href="/cmd/go/">go</a> command. -</p> - -<p> <!-- CL 31768, 31811 --> -If <a href="/cmd/cgo/">cgo</a> code calls <code>C.malloc</code>, and -<code>malloc</code> returns <code>NULL</code>, the program will now -crash with an out of memory error. -<code>C.malloc</code> will never return <code>nil</code>. -Unlike most C functions, <code>C.malloc</code> may not be used in a -two-result form returning an errno value. -</p> - -<p> <!-- CL 33237 --> -If <a href="/cmd/cgo/">cgo</a> is used to call a C function passing a -pointer to a C union, and if the C union can contain any pointer -values, and if <a href="/cmd/cgo/#hdr-Passing_pointers">cgo pointer -checking</a> is enabled (as it is by default), the union value is now -checked for Go pointers. -</p> - -<h3 id="gccgo">Gccgo</h3> - -<p> -Due to the alignment of Go's semiannual release schedule with GCC's -annual release schedule, -GCC release 6 contains the Go 1.6.1 version of gccgo. -We expect that the next release, GCC 7, will contain the Go 1.8 -version of gccgo. -</p> - -<h3 id="gopath">Default GOPATH</h3> - -<p> - The - <a href="/cmd/go/#hdr-GOPATH_environment_variable"><code>GOPATH</code> - environment variable</a> now has a default value if it - is unset. It defaults to - <code>$HOME/go</code> on Unix and - <code>%USERPROFILE%/go</code> on Windows. -</p> - -<h3 id="go_get">Go get</h3> - -<p> <!-- CL 34818 --> - The “<code>go</code> <code>get</code>” command now always respects - HTTP proxy environment variables, regardless of whether - the <code style='white-space:nowrap'>-insecure</code> flag is used. In previous releases, the - <code style='white-space:nowrap'>-insecure</code> flag had the side effect of not using proxies. -</p> - -<h3 id="go_bug">Go bug</h3> - -<p> - The new - “<a href="/cmd/go/#hdr-Print_information_for_bug_reports"><code>go</code> <code>bug</code></a>” - command starts a bug report on GitHub, prefilled - with information about the current system. -</p> - -<h3 id="cmd_doc">Go doc</h3> - -<p> <!-- CL 25419 --> - The - “<a href="/cmd/go/#hdr-Show_documentation_for_package_or_symbol"><code>go</code> <code>doc</code></a>” - command now groups constants and variables with their type, - following the behavior of - <a href="/cmd/godoc/"><code>godoc</code></a>. -</p> - -<p> <!-- CL 25420 --> - In order to improve the readability of <code>doc</code>'s - output, each summary of the first-level items is guaranteed to - occupy a single line. -</p> - -<p> <!-- CL 31852 --> - Documentation for a specific method in an interface definition can - now be requested, as in - “<code>go</code> <code>doc</code> <code>net.Conn.SetDeadline</code>”. -</p> - -<h3 id="plugin">Plugins</h3> - -<p> - Go now provides early support for plugins with a “<code>plugin</code>” - build mode for generating plugins written in Go, and a - new <a href="/pkg/plugin/"><code>plugin</code></a> package for - loading such plugins at run time. Plugin support is currently only - available on Linux. Please report any issues. -</p> - -<h2 id="runtime">Runtime</h2> - -<h3 id="liveness">Argument Liveness</h3> - -<p> - <!-- Issue 15843 --> The garbage collector no longer considers - arguments live throughout the entirety of a function. For more - information, and for how to force a variable to remain live, see - the <a href="/pkg/runtime/#KeepAlive"><code>runtime.KeepAlive</code></a> - function added in Go 1.7. -</p> - -<p> - <i>Updating:</i> - Code that sets a finalizer on an allocated object may need to add - calls to <code>runtime.KeepAlive</code> in functions or methods - using that object. - Read the - <a href="/pkg/runtime/#KeepAlive"><code>KeepAlive</code> - documentation</a> and its example for more details. -</p> - -<h3 id="mapiter">Concurrent Map Misuse</h3> - -<p> -In Go 1.6, the runtime -<a href="/doc/go1.6#runtime">added lightweight, -best-effort detection of concurrent misuse of maps</a>. This release -improves that detector with support for detecting programs that -concurrently write to and iterate over a map. -</p> -<p> -As always, if one goroutine is writing to a map, no other goroutine should be -reading (which includes iterating) or writing the map concurrently. -If the runtime detects this condition, it prints a diagnosis and crashes the program. -The best way to find out more about the problem is to run the program -under the -<a href="https://blog.golang.org/race-detector">race detector</a>, -which will more reliably identify the race -and give more detail. -</p> - -<h3 id="memstats">MemStats Documentation</h3> - -<p> <!-- CL 28972 --> - The <a href="/pkg/runtime/#MemStats"><code>runtime.MemStats</code></a> - type has been more thoroughly documented. -</p> - -<h2 id="performance">Performance</h2> - -<p> -As always, the changes are so general and varied that precise statements -about performance are difficult to make. -Most programs should run a bit faster, -due to speedups in the garbage collector and -optimizations in the standard library. -</p> - -<p> -There have been optimizations to implementations in the -<a href="/pkg/bytes/"><code>bytes</code></a>, -<a href="/pkg/crypto/aes/"><code>crypto/aes</code></a>, -<a href="/pkg/crypto/cipher/"><code>crypto/cipher</code></a>, -<a href="/pkg/crypto/elliptic/"><code>crypto/elliptic</code></a>, -<a href="/pkg/crypto/sha256/"><code>crypto/sha256</code></a>, -<a href="/pkg/crypto/sha512/"><code>crypto/sha512</code></a>, -<a href="/pkg/encoding/asn1/"><code>encoding/asn1</code></a>, -<a href="/pkg/encoding/csv/"><code>encoding/csv</code></a>, -<a href="/pkg/encoding/hex/"><code>encoding/hex</code></a>, -<a href="/pkg/encoding/json/"><code>encoding/json</code></a>, -<a href="/pkg/hash/crc32/"><code>hash/crc32</code></a>, -<a href="/pkg/image/color/"><code>image/color</code></a>, -<a href="/pkg/image/draw/"><code>image/draw</code></a>, -<a href="/pkg/math/"><code>math</code></a>, -<a href="/pkg/math/big/"><code>math/big</code></a>, -<a href="/pkg/reflect/"><code>reflect</code></a>, -<a href="/pkg/regexp/"><code>regexp</code></a>, -<a href="/pkg/runtime/"><code>runtime</code></a>, -<a href="/pkg/strconv/"><code>strconv</code></a>, -<a href="/pkg/strings/"><code>strings</code></a>, -<a href="/pkg/syscall/"><code>syscall</code></a>, -<a href="/pkg/text/template/"><code>text/template</code></a>, and -<a href="/pkg/unicode/utf8/"><code>unicode/utf8</code></a> -packages. -</p> - -<h3 id="gc">Garbage Collector</h3> - -<p> - Garbage collection pauses should be significantly shorter than they - were in Go 1.7, usually under 100 microseconds and often as low as - 10 microseconds. - See the - <a href="https://github.com/golang/proposal/blob/master/design/17503-eliminate-rescan.md" - >document on eliminating stop-the-world stack re-scanning</a> - for details. More work remains for Go 1.9. -</p> - -<h3 id="defer">Defer</h3> - -<!-- CL 29656, CL 29656 --> -<p> - The overhead of <a href="/ref/spec/#Defer_statements">deferred - function calls</a> has been reduced by about half. -</p> - -<h3 id="cgoperf">Cgo</h3> - -<p>The overhead of calls from Go into C has been reduced by about half.</p> - -<h2 id="library">Standard library</h2> - -<h3 id="examples">Examples</h3> - -<p> -Examples have been added to the documentation across many packages. -</p> - -<h3 id="sort_slice">Sort</h3> - -<p> -The <a href="/pkg/sort/">sort</a> package -now includes a convenience function -<a href="/pkg/sort/#Slice"><code>Slice</code></a> to sort a -slice given a <em>less</em> function. - -In many cases this means that writing a new sorter type is not -necessary. -</p> - -<p> -Also new are -<a href="/pkg/sort/#SliceStable"><code>SliceStable</code></a> and -<a href="/pkg/sort/#SliceIsSorted"><code>SliceIsSorted</code></a>. -</p> - -<h3 id="h2push">HTTP/2 Push</h3> - -<p> -The <a href="/pkg/net/http/">net/http</a> package now includes a -mechanism to -send HTTP/2 server pushes from a -<a href="/pkg/net/http/#Handler"><code>Handler</code></a>. -Similar to the existing <code>Flusher</code> and <code>Hijacker</code> -interfaces, an HTTP/2 -<a href="/pkg/net/http/#ResponseWriter"><code>ResponseWriter</code></a> -now implements the new -<a href="/pkg/net/http/#Pusher"><code>Pusher</code></a> interface. -</p> - -<h3 id="http_shutdown">HTTP Server Graceful Shutdown</h3> - -<p> <!-- CL 32329 --> - The HTTP Server now has support for graceful shutdown using the new - <a href="/pkg/net/http/#Server.Shutdown"><code>Server.Shutdown</code></a> - method and abrupt shutdown using the new - <a href="/pkg/net/http/#Server.Close"><code>Server.Close</code></a> - method. -</p> - -<h3 id="more_context">More Context Support</h3> - -<p> - Continuing <a href="/doc/go1.7#context">Go 1.7's adoption</a> - of <a href="/pkg/context/#Context"><code>context.Context</code></a> - into the standard library, Go 1.8 adds more context support - to existing packages: -</p> - -<ul> - <li>The new <a href="/pkg/net/http/#Server.Shutdown"><code>Server.Shutdown</code></a> - takes a context argument.</li> - <li>There have been <a href="#database_sql">significant additions</a> to the - <a href="/pkg/database/sql/">database/sql</a> package with context support.</li> - <li>All nine of the new <code>Lookup</code> methods on the new - <a href="/pkg/net/#Resolver"><code>net.Resolver</code></a> now - take a context.</li> - </ul> - -<h3 id="mutex_prof">Mutex Contention Profiling</h3> - -<p> - The runtime and tools now support profiling contended mutexes. -</p> - -<p> - Most users will want to use the new <code>-mutexprofile</code> - flag with “<a href="/cmd/go/#hdr-Description_of_testing_flags"><code>go</code> <code>test</code></a>”, - and then use <a href="/cmd/pprof/">pprof</a> on the resultant file. -</p> - -<p> - Lower-level support is also available via the new - <a href="/pkg/runtime/#MutexProfile"><code>MutexProfile</code></a> - and - <a href="/pkg/runtime/#SetMutexProfileFraction"><code>SetMutexProfileFraction</code></a>. -</p> - -<p> - A known limitation for Go 1.8 is that the profile only reports contention for - <a href="/pkg/sync/#Mutex"><code>sync.Mutex</code></a>, - not - <a href="/pkg/sync/#RWMutex"><code>sync.RWMutex</code></a>. -</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. The following sections list the user visible changes and additions. -Optimizations and minor bug fixes are not listed. -</p> - -<dl id="archive_tar"><dt><a href="/pkg/archive/tar/">archive/tar</a></dt> - <dd> - - <p> <!-- CL 28471, CL 31440, CL 31441, CL 31444, CL 28418, CL 31439 --> - The tar implementation corrects many bugs in corner cases of the file format. - The <a href="/pkg/archive/tar/#Reader"><code>Reader</code></a> - is now able to process tar files in the PAX format with entries larger than 8GB. - The <a href="/pkg/archive/tar/#Writer"><code>Writer</code></a> - no longer produces invalid tar files in some situations involving long pathnames. - </p> - - </dd> -</dl> - -<dl id="compress_flate"><dt><a href="/pkg/compress/flate/">compress/flate</a></dt> - <dd> - - <p> <!-- CL 31640, CL 31174, CL 32149 --> - There have been some minor fixes to the encoder to improve the - compression ratio in certain situations. As a result, the exact - encoded output of <code>DEFLATE</code> may be different from Go 1.7. Since - <code>DEFLATE</code> is the underlying compression of gzip, png, zlib, and zip, - those formats may have changed outputs. - </p> - - <p> <!-- CL 31174 --> - The encoder, when operating in - <a href="/pkg/compress/flate/#NoCompression"><code>NoCompression</code></a> - mode, now produces a consistent output that is not dependent on - the size of the slices passed to the - <a href="/pkg/compress/flate/#Writer.Write"><code>Write</code></a> - method. - </p> - - <p> <!-- CL 28216 --> - The decoder, upon encountering an error, now returns any - buffered data it had uncompressed along with the error. - </p> - - </dd> -</dl> - - -<dl id="compress_gzip"><dt><a href="/pkg/compress/gzip/">compress/gzip</a></dt> - <dd> - - <p> - The <a href="/pkg/compress/gzip/#Writer"><code>Writer</code></a> - now encodes a zero <code>MTIME</code> field when - the <a href="/pkg/compress/gzip/#Header"><code>Header.ModTime</code></a> - field is the zero value. - - In previous releases of Go, the <code>Writer</code> would encode - a nonsensical value. - - Similarly, - the <a href="/pkg/compress/gzip/#Reader"><code>Reader</code></a> - now reports a zero encoded <code>MTIME</code> field as a zero - <code>Header.ModTime</code>. - </p> - - </dd> -</dl> - -<dl id="context"><dt><a href="/pkg/context/">context</a></dt> - <dd> - <p> <!-- CL 30370 --> - The <a href="/pkg/context#DeadlineExceeded"><code>DeadlineExceeded</code></a> - error now implements - <a href="/pkg/net/#Error"><code>net.Error</code></a> - and reports true for both the <code>Timeout</code> and - <code>Temporary</code> methods. - </p> - </dd> -</dl> - -<dl id="crypto_tls"><dt><a href="/pkg/crypto/tls/">crypto/tls</a></dt> - <dd> - <p> <!-- CL 25159, CL 31318 --> - The new method - <a href="/pkg/crypto/tls/#Conn.CloseWrite"><code>Conn.CloseWrite</code></a> - allows TLS connections to be half closed. - </p> - - <p> <!-- CL 28075 --> - The new method - <a href="/pkg/crypto/tls/#Config.Clone"><code>Config.Clone</code></a> - clones a TLS configuration. - </p> - - <p> - <!-- CL 30790 --> - The new <a href="/pkg/crypto/tls/#Config.GetConfigForClient"><code>Config.GetConfigForClient</code></a> - callback allows selecting a configuration for a client dynamically, based - on the client's - <a href="/pkg/crypto/tls/#ClientHelloInfo"><code>ClientHelloInfo</code></a>. - - <!-- CL 31391, CL 32119 --> - The <a href="/pkg/crypto/tls/#ClientHelloInfo"><code>ClientHelloInfo</code></a> - struct now has new - fields <code>Conn</code>, <code>SignatureSchemes</code> (using - the new - type <a href="/kg/crypto/tls/#SignatureScheme"><code>SignatureScheme</code></a>), - <code>SupportedProtos</code>, and <code>SupportedVersions</code>. - </p> - - <p> <!-- CL 32115 --> - The new <a href="/pkg/crypto/tls/#Config.GetClientCertificate"><code>Config.GetClientCertificate</code></a> - callback allows selecting a client certificate based on the server's - TLS <code>CertificateRequest</code> message, represented by the new - <a href="/pkg/crypto/tls/#CertificateRequestInfo"><code>CertificateRequestInfo</code></a>. - </p> - - <p> <!-- CL 27434 --> - The new - <a href="/pkg/crypto/tls/#Config.KeyLogWriter"><code>Config.KeyLogWriter</code></a> - allows debugging TLS connections - in <a href="https://www.wireshark.org/">WireShark</a> and - similar tools. - </p> - - <p> <!-- CL 32115 --> - The new - <a href="/pkg/crypto/tls/#Config.VerifyPeerCertificate"><code>Config.VerifyPeerCertificate</code></a> - callback allows additional validation of a peer's presented certificate. - </p> - - <p> <!-- CL 18130 --> - The <code>crypto/tls</code> package now implements basic - countermeasures against CBC padding oracles. There should be - no explicit secret-dependent timings, but it does not attempt to - normalize memory accesses to prevent cache timing leaks. - </p> - - <p> - The <code>crypto/tls</code> package now supports - X25519 and <!-- CL 30824, CL 30825 --> - ChaCha20-Poly1305. <!-- CL 30957, CL 30958 --> - ChaCha20-Poly1305 is now prioritized unless <!-- CL 32871 --> - hardware support for AES-GCM is present. - </p> - - <p> <!-- CL 27315, CL 35290 --> - AES-128-CBC cipher suites with SHA-256 are also - now supported, but disabled by default. - </p> - - </dd> -</dl> - -<dl id="crypto_x509"><dt><a href="/pkg/crypto/x509/">crypto/x509</a></dt> - <dd> - <p> <!-- CL 24743 --> - PSS signatures are now supported. - </p> - - <p> <!-- CL 32644 --> - <a href="/pkg/crypto/x509/#UnknownAuthorityError"><code>UnknownAuthorityError</code></a> - now has a <code>Cert</code> field, reporting the untrusted - certificate. - </p> - - <p> - Certificate validation is more permissive in a few cases and - stricter in a few other cases. - <!-- -crypto/x509: allow a leaf certificate to be specified directly as root (CL 27393) -crypto/x509: check that the issuer name matches the issuer's subject name (CL 23571) -crypto/x509: don't accept a root that already appears in a chain. (CL 32121) -crypto/x509: fix name constraints handling (CL 30155) -crypto/x509: parse all names in an RDN (CL 30810) -crypto/x509: recognise ISO OID for RSA+SHA1 (CL 27394) -crypto/x509: require a NULL parameters for RSA public keys (CL 16166, CL 27312) -crypto/x509: return error for missing SerialNumber (CL 27238) ---> - </p> - - <p><!-- CL 30375 --> - Root certificates will now also be looked for - at <code>/etc/pki/ca-trust/extracted/pem/tls-ca-bundle.pem</code> - on Linux, to support RHEL and CentOS. - </p> - - </dd> -</dl> - -<dl id="database_sql"><dt><a href="/pkg/database/sql/">database/sql</a></dt> - <dd> - <p> - The package now supports <code>context.Context</code>. There are new methods - ending in <code>Context</code> such as - <a href="/pkg/database/sql/#DB.QueryContext"><code>DB.QueryContext</code></a> and - <a href="/pkg/database/sql/#DB.PrepareContext"><code>DB.PrepareContext</code></a> - that take context arguments. Using the new <code>Context</code> methods ensures that - connections are closed and returned to the connection pool when the - request is done; enables canceling in-progress queries - should the driver support that; and allows the database - pool to cancel waiting for the next available connection. - </p> - <p> - The <a href="/pkg/database/sql#IsolationLevel"><code>IsolationLevel</code></a> - can now be set when starting a transaction by setting the isolation level - on <a href="/pkg/database/sql#TxOptions.Isolation"><code>TxOptions.Isolation</code></a> and passing - it to <a href="/pkg/database/sql#DB.BeginTx"><code>DB.BeginTx</code></a>. - An error will be returned if an isolation level is selected that the driver - does not support. A read-only attribute may also be set on the transaction - by setting <a href="/pkg/database/sql/#TxOptions.ReadOnly"><code>TxOptions.ReadOnly</code></a> - to true. - </p> - <p> - Queries now expose the SQL column type information for drivers that support it. - Rows can return <a href="/pkg/database/sql#Rows.ColumnTypes"><code>ColumnTypes</code></a> - which can include SQL type information, column type lengths, and the Go type. - </p> - <p> - A <a href="/pkg/database/sql/#Rows"><code>Rows</code></a> - can now represent multiple result sets. After - <a href="/pkg/database/sql/#Rows.Next"><code>Rows.Next</code></a> returns false, - <a href="/pkg/database/sql/#Rows.NextResultSet"><code>Rows.NextResultSet</code></a> - may be called to advance to the next result set. The existing <code>Rows</code> - should continue to be used after it advances to the next result set. - </p> - <p> - <a href="/pkg/database/sql/#NamedArg"><code>NamedArg</code></a> may be used - as query arguments. The new function <a href="/pkg/database/sql/#Named"><code>Named</code></a> - helps create a <a href="/pkg/database/sql/#NamedArg"><code>NamedArg</code></a> - more succinctly. - <p> - If a driver supports the new - <a href="/pkg/database/sql/driver/#Pinger"><code>Pinger</code></a> - interface, the - <a href="/pkg/database/sql/#DB.Ping"><code>DB.Ping</code></a> - and - <a href="/pkg/database/sql/#DB.PingContext"><code>DB.PingContext</code></a> - methods will use that interface to check whether a - database connection is still valid. - </p> - <p> - The new <code>Context</code> query methods work for all drivers, but - <code>Context</code> cancelation is not responsive unless the driver has been - updated to use them. The other features require driver support in - <a href="/pkg/database/sql/driver"><code>database/sql/driver</code></a>. - Driver authors should review the new interfaces. Users of existing - driver should review the driver documentation to see what - it supports and any system specific documentation on each feature. - </p> - </dd> -</dl> - -<dl id="debug_pe"><dt><a href="/pkg/debug/pe/">debug/pe</a></dt> - <dd> - <p> <!-- CL 22720, CL 27212, CL 22181, CL 22332, CL 22336, Issue 15345 --> - The package has been extended and is now used by - <a href="/cmd/link/">the Go linker</a> to read <code>gcc</code>-generated object files. - The new - <a href="/pkg/debug/pe/#File.StringTable"><code>File.StringTable</code></a> - and - <a href="/pkg/debug/pe/#Section.Relocs"><code>Section.Relocs</code></a> - fields provide access to the COFF string table and COFF relocations. - The new - <a href="/pkg/debug/pe/#File.COFFSymbols"><code>File.COFFSymbols</code></a> - allows low-level access to the COFF symbol table. - </p> - </dd> -</dl> - -<dl id="encoding_base64"><dt><a href="/pkg/encoding/base64/">encoding/base64</a></dt> - <dd> - <p> <!-- CL 24964 --> - The new - <a href="/pkg/encoding/base64/#Encoding.Strict"><code>Encoding.Strict</code></a> - method returns an <code>Encoding</code> that causes the decoder - to return an error when the trailing padding bits are not zero. - </p> - </dd> -</dl> - -<dl id="encoding_binary"><dt><a href="/pkg/encoding/binary/">encoding/binary</a></dt> - <dd> - <p> <!-- CL 28514 --> - <a href="/pkg/encoding/binary/#Read"><code>Read</code></a> - and - <a href="/pkg/encoding/binary/#Write"><code>Write</code></a> - now support booleans. - </p> - </dd> -</dl> - -<dl id="encoding_json"><dt><a href="/pkg/encoding/json/">encoding/json</a></dt> - <dd> - - <p> <!-- CL 18692 --> - <a href="/pkg/encoding/json/#UnmarshalTypeError"><code>UnmarshalTypeError</code></a> - now includes the struct and field name. - </p> - - <p> <!-- CL 31932 --> - A nil <a href="/pkg/encoding/json/#Marshaler"><code>Marshaler</code></a> - now marshals as a JSON <code>null</code> value. - </p> - - <p> <!-- CL 21811 --> - A <a href="/pkg/encoding/json/#RawMessage"><code>RawMessage</code></a> value now - marshals the same as its pointer type. - </p> - - <p> <!-- CL 30371 --> - <a href="/pkg/encoding/json/#Marshal"><code>Marshal</code></a> - encodes floating-point numbers using the same format as in ES6, - preferring decimal (not exponential) notation for a wider range of values. - In particular, all floating-point integers up to 2<sup>64</sup> format the - same as the equivalent <code>int64</code> representation. - </p> - - <p> <!-- CL 30944 --> - In previous versions of Go, unmarshaling a JSON <code>null</code> into an - <a href="/pkg/encoding/json/#Unmarshaler"><code>Unmarshaler</code></a> - was considered a no-op; now the <code>Unmarshaler</code>'s - <code>UnmarshalJSON</code> method is called with the JSON literal - <code>null</code> and can define the semantics of that case. - </p> - - </dd> -</dl> - -<dl id="encoding_pem"><dt><a href="/pkg/encoding/pem/">encoding/pem</a></dt> - <dd> - <p> <!-- CL 27391 --> - <a href="/pkg/encoding/pem/#Decode"><code>Decode</code></a> - is now strict about the format of the ending line. - </p> - </dd> -</dl> - -<dl id="encoding_xml"><dt><a href="/pkg/encoding/xml/">encoding/xml</a></dt> - <dd> - <p> <!-- CL 30946 --> - <a href="/pkg/encoding/xml/#Unmarshal"><code>Unmarshal</code></a> - now has wildcard support for collecting all attributes using - the new <code>",any,attr"</code> struct tag. - </p> - </dd> -</dl> - -<dl id="expvar"><dt><a href="/pkg/expvar/">expvar</a></dt> - <dd> - <p> <!-- CL 30917 --> - The new methods - <a href="/pkg/expvar/#Int.Value"><code>Int.Value</code></a>, - <a href="/pkg/expvar/#String.Value"><code>String.Value</code></a>, - <a href="/pkg/expvar/#Float.Value"><code>Float.Value</code></a>, and - <a href="/pkg/expvar/#Func.Value"><code>Func.Value</code></a> - report the current value of an exported variable. - </p> - - <p> <!-- CL 24722 --> - The new - function <a href="/pkg/expvar/#Handler"><code>Handler</code></a> - returns the package's HTTP handler, to enable installing it in - non-standard locations. - </p> - </dd> -</dl> - -<dl id="fmt"><dt><a href="/pkg/fmt/">fmt</a></dt> - <dd> - <p><!-- CL 30611 --> - <a href="/pkg/fmt/#Scanf"><code>Scanf</code></a>, - <a href="/pkg/fmt/#Fscanf"><code>Fscanf</code></a>, and - <a href="/pkg/fmt/#Sscanf"><code>Sscanf</code></a> now - handle spaces differently and more consistently than - previous releases. See the - <a href="/pkg/fmt/#hdr-Scanning">scanning documentation</a> - for details. - </p> - </dd> -</dl> - -<dl id="go_doc"><dt><a href="/pkg/go/doc/">go/doc</a></dt> - <dd> - <p><!-- CL 29870 --> - The new <a href="/pkg/go/doc/#IsPredeclared"><code>IsPredeclared</code></a> - function reports whether a string is a predeclared identifier. - </p> - </dd> -</dl> - -<dl id="go_types"><dt><a href="/pkg/go/types/">go/types</a></dt> - <dd> - <p><!-- CL 30715 --> - The new function - <a href="/pkg/go/types/#Default"><code>Default</code></a> - returns the default "typed" type for an "untyped" type. - </p> - - <p><!-- CL 31939 --> - The alignment of <code>complex64</code> now matches - the <a href="/cmd/compile/">Go compiler</a>. - </p> - </dd> -</dl> - -<dl id="html_template"><dt><a href="/pkg/html/template/">html/template</a></dt> - <dd> - <p><!-- CL 14336 --> - The package now validates - the <code>"type"</code> attribute on - a <code><script></code> tag. - </p> - </dd> -</dl> - -<dl id="image_png"><dt><a href="/pkg/image/png/">image/png</a></dt> - <dd> - <p> <!-- CL 32143, CL 32140 --> - <a href="/pkg/image/png/#Decode"><code>Decode</code></a> - (and <code>DecodeConfig</code>) - now supports True Color and grayscale transparency. - </p> - <p> <!-- CL 29872 --> - <a href="/pkg/image/png/#Encoder"><code>Encoder</code></a> - is now faster and creates smaller output - when encoding paletted images. - </p> - </dd> -</dl> - -<dl id="math_big"><dt><a href="/pkg/math/big/">math/big</a></dt> - <dd> - <p><!-- CL 30706 --> - The new method - <a href="/pkg/math/big/#Int.Sqrt"><code>Int.Sqrt</code></a> - calculates ⌊√x⌋. - </p> - - <p> - The new method - <a href="/pkg/math/big/#Float.Scan"><code>Float.Scan</code></a> - is a support routine for - <a href="/pkg/fmt/#Scanner"><code>fmt.Scanner</code></a>. - </p> - - <p> - <a href="/pkg/math/big/#Int.ModInverse"><code>Int.ModInverse</code></a> - now supports negative numbers. - </p> - - </dd> -</dl> - -<dl id="math_rand"><dt><a href="/pkg/math/rand/">math/rand</a></dt> - <dd> - - <p><!-- CL 27253, CL 33456 --> - The new <a href="/pkg/math/rand/#Rand.Uint64"><code>Rand.Uint64</code></a> - method returns <code>uint64</code> values. The - new <a href="/pkg/math/rand/#Source64"><code>Source64</code></a> - interface describes sources capable of generating such values - directly; otherwise the <code>Rand.Uint64</code> method - constructs a <code>uint64</code> from two calls - to <a href="/pkg/math/rand/#Source"><code>Source</code></a>'s - <code>Int63</code> method. - </p> - - </dd> -</dl> - -<dl id="mime"><dt><a href="/pkg/mime/">mime</a></dt> - <dd> - <p> <!-- CL 32175 --> - <a href="/pkg/mime/#ParseMediaType"><code>ParseMediaType</code></a> - now preserves unnecessary backslash escapes as literals, - in order to support MSIE. - When MSIE sends a full file path (in “intranet mode”), it does not - escape backslashes: “<code>C:\dev\go\foo.txt</code>”, not - “<code>C:\\dev\\go\\foo.txt</code>”. - If we see an unnecessary backslash escape, we now assume it is from MSIE - and intended as a literal backslash. - No known MIME generators emit unnecessary backslash escapes - for simple token characters like numbers and letters. - </p> - </dd> -</dl> - -<dl id="mime_quotedprintable"><dt><a href="/pkg/mime/quotedprintable/">mime/quotedprintable</a></dt> - <dd> - - <p> - The - <a href="/pkg/mime/quotedprintable/#Reader"><code>Reader</code></a>'s - parsing has been relaxed in two ways to accept - more input seen in the wild. - - <!-- CL 32174 --> - First, it accepts an equals sign (<code>=</code>) not followed - by two hex digits as a literal equal sign. - - <!-- CL 27530 --> - Second, it silently ignores a trailing equals sign at the end of - an encoded input. - </p> - - </dd> -</dl> - -<dl id="net"><dt><a href="/pkg/net/">net</a></dt> - <dd> - - <p><!-- CL 30164, CL 33473 --> - The <a href="/pkg/net/#Conn"><code>Conn</code></a> documentation - has been updated to clarify expectations of an interface - implementation. Updates in the <code>net/http</code> packages - depend on implementations obeying the documentation. - </p> - <p><i>Updating:</i> implementations of the <code>Conn</code> interface should verify - they implement the documented semantics. The - <a href="https://godoc.org/golang.org/x/net/nettest">golang.org/x/net/nettest</a> - package will exercise a <code>Conn</code> and validate it behaves properly. - </p> - - <p><!-- CL 32099 --> - The new method - <a href="/pkg/net/#UnixListener.SetUnlinkOnClose"><code>UnixListener.SetUnlinkOnClose</code></a> - sets whether the underlying socket file should be removed from the file system when - the listener is closed. - </p> - - <p><!-- CL 29951 --> - The new <a href="/pkg/net/#Buffers"><code>Buffers</code></a> type permits - writing to the network more efficiently from multiple discontiguous buffers - in memory. On certain machines, for certain types of connections, - this is optimized into an OS-specific batch write operation (such as <code>writev</code>). - </p> - - <p><!-- CL 29440 --> - The new <a href="/pkg/net/#Resolver"><code>Resolver</code></a> looks up names and numbers - and supports <a href="/pkg/context/#Context"><code>context.Context</code></a>. - The <a href="/pkg/net/#Dialer"><code>Dialer</code></a> now has an optional - <a href="/pkg/net/#Dialer.Resolver"><code>Resolver</code> field</a>. - </p> - - <p><!-- CL 29892 --> - <a href="/pkg/net/#Interfaces"><code>Interfaces</code></a> is now supported on Solaris. - </p> - - <p><!-- CL 29233, CL 24901 --> - The Go DNS resolver now supports <code>resolv.conf</code>'s “<code>rotate</code>” - and “<code>option</code> <code>ndots:0</code>” options. The “<code>ndots</code>” option is - now respected in the same way as <code>libresolve</code>. - </p> - - </dd> -</dl> - -<dl id="net_http"><dt><a href="/pkg/net/http/">net/http</a></dt> - <dd> - - <p>Server changes:</p> - <ul> - <li>The server now supports graceful shutdown support, <a href="#http_shutdown">mentioned above</a>.</li> - - <li> <!-- CL 32024 --> - The <a href="/pkg/net/http/#Server"><code>Server</code></a> - adds configuration options - <code>ReadHeaderTimeout</code> and <code>IdleTimeout</code> - and documents <code>WriteTimeout</code>. - </li> - - <li> <!-- CL 32014 --> - <a href="/pkg/net/http/#FileServer"><code>FileServer</code></a> - and - <a href="/pkg/net/http/#ServeContent"><code>ServeContent</code></a> - now support HTTP <code>If-Match</code> conditional requests, - in addition to the previous <code>If-None-Match</code> - support for ETags properly formatted according to RFC 7232, section 2.3. - </li> - </ul> - - <p> - There are several additions to what a server's <code>Handler</code> can do: - </p> - - <ul> - <li><!-- CL 31173 --> - The <a href="/pkg/context/#Context"><code>Context</code></a> - returned - by <a href="/pkg/net/http/#Request.Context"><code>Request.Context</code></a> - is canceled if the underlying <code>net.Conn</code> - closes. For instance, if the user closes their browser in the - middle of a slow request, the <code>Handler</code> can now - detect that the user is gone. This complements the - existing <a href="/pkg/net/http/#CloseNotifier"><code>CloseNotifier</code></a> - support. This functionality requires that the underlying - <a href="/pkg/net/#Conn"><code>net.Conn</code></a> implements - <a href="#net">recently clarified interface documentation</a>. - </li> - - <li><!-- CL 32479 --> - To serve trailers produced after the header has already been written, - see the new - <a href="/pkg/net/http/#TrailerPrefix"><code>TrailerPrefix</code></a> - mechanism. - </li> - - <li><!-- CL 33099 --> - A <code>Handler</code> can now abort a response by panicking - with the error - <a href="/pkg/net/http/#ErrAbortHandler"><code>ErrAbortHandler</code></a>. - </li> - - <li><!-- CL 30812 --> - A <code>Write</code> of zero bytes to a - <a href="/pkg/net/http/#ResponseWriter"><code>ResponseWriter</code></a> - is now defined as a - way to test whether a <code>ResponseWriter</code> has been hijacked: - if so, the <code>Write</code> returns - <a href="/pkg/net/http/#ErrHijacked"><code>ErrHijacked</code></a> - without printing an error - to the server's error log. - </li> - - </ul> - - <p>Client & Transport changes:</p> - <ul> - <li><!-- CL 28930, CL 31435 --> - The <a href="/pkg/net/http/#Client"><code>Client</code></a> - now copies most request headers on redirect. See - <a href="/pkg/net/http/#Client">the documentation</a> - on the <code>Client</code> type for details. - </li> - - <li><!-- CL 29072 --> - The <a href="/pkg/net/http/#Transport"><code>Transport</code></a> - now supports international domain names. Consequently, so do - <a href="/pkg/net/http/#Get">Get</a> and other helpers. - </li> - - <li><!-- CL 31733, CL 29852 --> - The <code>Client</code> now supports 301, 307, and 308 redirects. - - For example, <code>Client.Post</code> now follows 301 - redirects, converting them to <code>GET</code> requests - without bodies, like it did for 302 and 303 redirect responses - previously. - - The <code>Client</code> now also follows 307 and 308 - redirects, preserving the original request method and body, if - any. If the redirect requires resending the request body, the - request must have the new - <a href="/pkg/net/http/#Request"><code>Request.GetBody</code></a> - field defined. - <a href="/pkg/net/http/#NewRequest"><code>NewRequest</code></a> - sets <code>Request.GetBody</code> automatically for common - body types. - </li> - - <li><!-- CL 32482 --> - The <code>Transport</code> now rejects requests for URLs with - ports containing non-digit characters. - </li> - - <li><!-- CL 27117 --> - The <code>Transport</code> will now retry non-idempotent - requests if no bytes were written before a network failure - and the request has no body. - </li> - - <li><!-- CL 32481 --> - The - new <a href="/pkg/net/http/#Transport"><code>Transport.ProxyConnectHeader</code></a> - allows configuration of header values to send to a proxy - during a <code>CONNECT</code> request. - </li> - - <li> <!-- CL 28077 --> - The <a href="/pkg/net/http/#DefaultTransport"><code>DefaultTransport.Dialer</code></a> - now enables <code>DualStack</code> ("<a href="https://tools.ietf.org/html/rfc6555">Happy Eyeballs</a>") support, - allowing the use of IPv4 as a backup if it looks like IPv6 might be - failing. - </li> - - <li> <!-- CL 31726 --> - The <a href="/pkg/net/http/#Transport"><code>Transport</code></a> - no longer reads a byte of a non-nil - <a href="/pkg/net/http/#Request.Body"><code>Request.Body</code></a> - when the - <a href="/pkg/net/http/#Request.ContentLength"><code>Request.ContentLength</code></a> - is zero to determine whether the <code>ContentLength</code> - is actually zero or just undefined. - To explicitly signal that a body has zero length, - either set it to <code>nil</code>, or set it to the new value - <a href="/pkg/net/http/#NoBody"><code>NoBody</code></a>. - The new <code>NoBody</code> value is intended for use by <code>Request</code> - constructor functions; it is used by - <a href="/pkg/net/http/#NewRequest"><code>NewRequest</code></a>. - </li> - </ul> - - </dd> -</dl> - -<dl id="net_http_httptrace"><dt><a href="/pkg/net/http/httptrace/">net/http/httptrace</a></dt> - <dd> - <p> <!-- CL 30359 --> - There is now support for tracing a client request's TLS handshakes with - the new - <a href="/pkg/net/http/httptrace/#ClientTrace.TLSHandshakeStart"><code>ClientTrace.TLSHandshakeStart</code></a> - and - <a href="/pkg/net/http/httptrace/#ClientTrace.TLSHandshakeDone"><code>ClientTrace.TLSHandshakeDone</code></a>. - </p> - </dd> -</dl> - -<dl id="net_http_httputil"><dt><a href="/pkg/net/http/httputil/">net/http/httputil</a></dt> - <dd> - <p> <!-- CL 32356 --> - The <a href="/pkg/net/http/httputil/#ReverseProxy"><code>ReverseProxy</code></a> - has a new optional hook, - <a href="/pkg/net/http/httputil/#ReverseProxy.ModifyResponse"><code>ModifyResponse</code></a>, - for modifying the response from the back end before proxying it to the client. - </p> - - </dd> -</dl> - -<dl id="net_mail"><dt><a href="/pkg/net/mail/">net/mail</a></dt> - <dd> - - <p> <!-- CL 32176 --> - Empty quoted strings are once again allowed in the name part of - an address. That is, Go 1.4 and earlier accepted - <code>""</code> <code><gopher@example.com></code>, - but Go 1.5 introduced a bug that rejected this address. - The address is recognized again. - </p> - - <p> <!-- CL 31581 --> - The - <a href="/pkg/net/mail/#Header.Date"><code>Header.Date</code></a> - method has always provided a way to parse - the <code>Date:</code> header. - A new function - <a href="/pkg/net/mail/#ParseDate"><code>ParseDate</code></a> - allows parsing dates found in other - header lines, such as the <code>Resent-Date:</code> header. - </p> - - </dd> -</dl> - -<dl id="net_smtp"><dt><a href="/pkg/net/smtp/">net/smtp</a></dt> - <dd> - - <p> <!-- CL 33143 --> - If an implementation of the - <a href="/pkg/net/smtp/#Auth"><code>Auth.Start</code></a> - method returns an empty <code>toServer</code> value, - the package no longer sends - trailing whitespace in the SMTP <code>AUTH</code> command, - which some servers rejected. - </p> - - </dd> -</dl> - -<dl id="net_url"><dt><a href="/pkg/net/url/">net/url</a></dt> - <dd> - - <p> <!-- CL 31322 --> - The new functions - <a href="/pkg/net/url/#PathEscape"><code>PathEscape</code></a> - and - <a href="/pkg/net/url/#PathUnescape"><code>PathUnescape</code></a> - are similar to the query escaping and unescaping functions but - for path elements. - </p> - - <p> <!-- CL 28933 --> - The new methods - <a href="/pkg/net/url/#URL.Hostname"><code>URL.Hostname</code></a> - and - <a href="/pkg/net/url/#URL.Port"><code>URL.Port</code></a> - return the hostname and port fields of a URL, - correctly handling the case where the port may not be present. - </p> - - <p> <!-- CL 28343 --> - The existing method - <a href="/pkg/net/url/#URL.ResolveReference"><code>URL.ResolveReference</code></a> - now properly handles paths with escaped bytes without losing - the escaping. - </p> - - <p> <!-- CL 31467 --> - The <code>URL</code> type now implements - <a href="/pkg/encoding/#BinaryMarshaler"><code>encoding.BinaryMarshaler</code></a> and - <a href="/pkg/encoding/#BinaryUnmarshaler"><code>encoding.BinaryUnmarshaler</code></a>, - making it possible to process URLs in <a href="/pkg/encoding/gob/">gob data</a>. - </p> - - <p> <!-- CL 29610, CL 31582 --> - Following RFC 3986, - <a href="/pkg/net/url/#Parse"><code>Parse</code></a> - now rejects URLs like <code>this_that:other/thing</code> instead of - interpreting them as relative paths (<code>this_that</code> is not a valid scheme). - To force interpretation as a relative path, - such URLs should be prefixed with “<code>./</code>”. - The <code>URL.String</code> method now inserts this prefix as needed. - </p> - - </dd> -</dl> - -<dl id="os"><dt><a href="/pkg/os/">os</a></dt> - <dd> - <p> <!-- CL 16551 --> - The new function - <a href="/pkg/os/#Executable"><code>Executable</code></a> returns - the path name of the running executable. - </p> - - <p> <!-- CL 30614 --> - An attempt to call a method on - an <a href="/pkg/os/#File"><code>os.File</code></a> that has - already been closed will now return the new error - value <a href="/pkg/os/#ErrClosed"><code>os.ErrClosed</code></a>. - Previously it returned a system-specific error such - as <code>syscall.EBADF</code>. - </p> - - <p> <!-- CL 31358 --> - On Unix systems, <a href="/pkg/os/#Rename"><code>os.Rename</code></a> - will now return an error when used to rename a directory to an - existing empty directory. - Previously it would fail when renaming to a non-empty directory - but succeed when renaming to an empty directory. - This makes the behavior on Unix correspond to that of other systems. - </p> - - <p> <!-- CL 32451 --> - On Windows, long absolute paths are now transparently converted to - extended-length paths (paths that start with “<code>\\?\</code>”). - This permits the package to work with files whose path names are - longer than 260 characters. - </p> - - <p> <!-- CL 29753 --> - On Windows, <a href="/pkg/os/#IsExist"><code>os.IsExist</code></a> - will now return <code>true</code> for the system - error <code>ERROR_DIR_NOT_EMPTY</code>. - This roughly corresponds to the existing handling of the Unix - error <code>ENOTEMPTY</code>. - </p> - - <p> <!-- CL 32152 --> - On Plan 9, files that are not served by <code>#M</code> will now - have <a href="/pkg/os/#ModeDevice"><code>ModeDevice</code></a> set in - the value returned - by <a href="/pkg/os/#FileInfo"><code>FileInfo.Mode</code></a>. - </p> - </dd> -</dl> - -<dl id="path_filepath"><dt><a href="/pkg/path/filepath/">path/filepath</a></dt> - <dd> - <p> - A number of bugs and corner cases on Windows were fixed: - <a href="/pkg/path/filepath/#Abs"><code>Abs</code></a> now calls <code>Clean</code> as documented, - <a href="/pkg/path/filepath/#Glob"><code>Glob</code></a> now matches - “<code>\\?\c:\*</code>”, - <a href="/pkg/path/filepath/#EvalSymlinks"><code>EvalSymlinks</code></a> now - correctly handles “<code>C:.</code>”, and - <a href="/pkg/path/filepath/#Clean"><code>Clean</code></a> now properly - handles a leading “<code>..</code>” in the path. - </p> - </dd> -</dl> - -<dl id="reflect"><dt><a href="/pkg/reflect/">reflect</a></dt> - <dd> - <p> <!-- CL 30088 --> - The new function - <a href="/pkg/reflect/#Swapper"><code>Swapper</code></a> was - added to support <a href="#sortslice"><code>sort.Slice</code></a>. - </p> - </dd> -</dl> - -<dl id="strconv"><dt><a href="/pkg/strconv/">strconv</a></dt> - <dd> - <p> <!-- CL 31210 --> - The <a href="/pkg/strconv/#Unquote"><code>Unquote</code></a> - function now strips carriage returns (<code>\r</code>) in - backquoted raw strings, following the - <a href="/ref/spec#String_literals">Go language semantics</a>. - </p> - </dd> -</dl> - -<dl id="syscall"><dt><a href="/pkg/syscall/">syscall</a></dt> - <dd> - <p> <!-- CL 25050, CL 25022 --> - The <a href="/pkg/syscall/#Getpagesize"><code>Getpagesize</code></a> - now returns the system's size, rather than a constant value. - Previously it always returned 4KB. - </p> - - <p> <!-- CL 31446 --> - The signature - of <a href="/pkg/syscall/#Utimes"><code>Utimes</code></a> has - changed on Solaris to match all the other Unix systems' - signature. Portable code should continue to use - <a href="/pkg/os/#Chtimes"><code>os.Chtimes</code></a> instead. - </p> - - <p> <!-- CL 32319 --> - The <code>X__cmsg_data</code> field has been removed from - <a href="/pkg/syscall/#Cmsghdr"><code>Cmsghdr</code></a>. - </p> - </dd> -</dl> - -<dl id="text_template"><dt><a href="/pkg/text/template/">text/template</a></dt> - <dd> - <p> <!-- CL 31462 --> - <a href="/pkg/text/template/#Template.Execute"><code>Template.Execute</code></a> - can now take a - <a href="/pkg/reflect/#Value"><code>reflect.Value</code></a> as its data - argument, and - <a href="/pkg/text/template/#FuncMap"><code>FuncMap</code></a> - functions can also accept and return <code>reflect.Value</code>. - </p> - - </dd> -</dl> - -<dl id="time"><dt><a href="/pkg/time/">time</a></dt> - <dd> - - <p> <!-- CL 20118 --> The new function - <a href="/pkg/time/#Until"><code>Until</code></a> complements - the analogous <code>Since</code> function. - </p> - - <p> <!-- CL 29338 --> - <a href="/pkg/time/#ParseDuration"><code>ParseDuration</code></a> - now accepts long fractional parts. - </p> - - <p> <!-- CL 33429 --> - <a href="/pkg/time/#Parse"><code>Parse</code></a> - now rejects dates before the start of a month, such as June 0; - it already rejected dates beyond the end of the month, such as - June 31 and July 32. - </p> - - <p> <!-- CL 33029 --> <!-- CL 34816 --> - The <code>tzdata</code> database has been updated to version - 2016j for systems that don't already have a local time zone - database. - </p> - - <p> - </dd> -</dl> - -<dl id="testing"><dt><a href="/pkg/testing/">testing</a></dt> - <dd> - <p><!-- CL 29970 --> - The new method - <a href="/pkg/testing/#T.Name"><code>T.Name</code></a> - (and <code>B.Name</code>) returns the name of the current - test or benchmark. - </p> - - <p><!-- CL 32483 --> - The new function - <a href="/pkg/testing/#CoverMode"><code>CoverMode</code></a> - reports the test coverage mode. - </p> - - <p><!-- CL 32615 --> - Tests and benchmarks are now marked as failed if the race - detector is enabled and a data race occurs during execution. - Previously, individual test cases would appear to pass, - and only the overall execution of the test binary would fail. - </p> - - <p><!-- CL 32455 --> - The signature of the - <a href="/pkg/testing/#MainStart"><code>MainStart</code></a> - function has changed, as allowed by the documentation. It is an - internal detail and not part of the Go 1 compatibility promise. - If you're not calling <code>MainStart</code> directly but see - errors, that likely means you set the - normally-empty <code>GOROOT</code> environment variable and it - doesn't match the version of your <code>go</code> command's binary. - </p> - - </dd> -</dl> - -<dl id="unicode"><dt><a href="/pkg/unicode/">unicode</a></dt> - <dd> - <p><!-- CL 30935 --> - <a href="/pkg/unicode/#SimpleFold"><code>SimpleFold</code></a> - now returns its argument unchanged if the provided input was an invalid rune. - Previously, the implementation failed with an index bounds check panic. - </p> - </dd> -</dl> |