doc/go1.11.html

<!--{
	"Title": "Go 1.11 Release Notes",
	"Path":  "/doc/go1.11",
	"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>
  ul li { margin: 0.5em 0; }
</style>

<h2 id="introduction">DRAFT RELEASE NOTES - Introduction to Go 1.11</h2>

<p>
  <strong>
    Go 1.11 is not yet released. These are work-in-progress
    release notes. Go 1.11 is expected to be released in August 2018.
  </strong>
</p>

<p>
  The latest Go release, version 1.11, arrives six months after <a href="go1.10">Go 1.10</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>

<h2 id="language">Changes to the language</h2>

<p>
  There are no changes to the language specification.
</p>

<h2 id="ports">Ports</h2>

<p>
  As <a href="go1.10#ports">announced in the Go 1.10 release notes</a>, Go 1.11 now requires
  OpenBSD 6.2 or later, macOS 10.10 Yosemite or later, or Windows 7 or later;
  Support for previous versions of these operating systems has been removed.
</p>

<p>
  There are <a href="https://golang.org/issue/25206">known issues</a> with NetBSD on i386 hardware.
</p>

<p><!-- CL 107935 -->
  TODO: PPC64LE race detector support
</p>

<h3 id="wasm">WebAssembly</h3>
<p>
  Go 1.11 adds an experimental port to WebAssembly (<code>js/wasm</code>).
</p>
<p>
  As a result of the addition of the new <code>GOOS</code> value
  "<code>js</code>" and <code>GOARCH</code> value "<code>wasm</code>",
  Go files named <code>*_js.go</code> or <code>*_wasm.go</code> will
  now be <a href="/pkg/go/build/#hdr-Build_Constraints">ignored by Go
  tools</a> except when those GOOS/GOARCH values are being used.
  If you have existing filenames matching those patterns, you will need to rename them.
</p>

<h2 id="tools">Tools</h2>

<h3 id="modules">Modules, package versioning, and dependency management</h3>
<p>
  <strong>
    NOTE: This is not present in go1.11beta1 but will be available in future
    betas and subsequent releases.
  </strong>
  Go 1.11 adds experimental support for a new concept called “modules,”
  an alternative to GOPATH with integrated support for versioning and
  package distribution.
  Using modules, developers are no longer confined to working inside GOPATH,
  version dependency information is explicit yet lightweight,
  and builds are more reliable and reproducible.
</p>

<p>
  Module support is considered experimental.
  Details are likely to change in response to feedback from Go 1.11 users,
  and we have more tools planned.
  Although the details of module support may change, projects that convert
  to modules using Go 1.11 will continue to work with Go 1.12 and later.
  If you encounter bugs using modules,
  please <a href="https://golang.org/issue/new">file issues</a>
  so we can fix them.
</p>

<p>
  TODO: Link to intro doc.  
</p>

<h3 id="importpath">Import path restriction</h3>

<p>
  Because Go module support assigns special meaning to the
  <code>@</code> symbol in command line operations,
  the <code>go</code> command now disallows the use of
  import paths containing <code>@</code> symbols.
  Such import paths were never allowed by <code>go</code> <code>get</code>,
  so this restriction can only affect users building
  custom GOPATH trees by other means.
</p>

<h3 id="gopackages">Package loading</h2>

<p>
  TODO: Note about go/build versus golang.org/x/tools/go/packages.
</p>

<h3 id="gocache">Build cache requirement</h2>

<p>
  Go 1.11 will be the last release to support setting the environment
  variable <code>GOCACHE=off</code> to disable the
  <a href="/cmd/go/#hdr-Build_and_test_caching">build cache</a>,
  introduced in Go 1.10.
  Starting in Go 1.12, the build cache will be required,
  as a step toward eliminating <code>$GOPATH/pkg</code>.
  The module and package loading support described above
  already require that the build cache be enabled.
  If you have disabled the build cache to avoid problems you encountered,
  please <a href="https://golang.org/issue/new">file an issue</a> to let us know about them.
</p>

<h2 id="library">Core library</h2>

<p>
  All of the changes to the standard library are minor.
</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>

<!-- CL 113315: https://golang.org/cl/113315: cmd/asm: enable AVX512 -->
<!-- CL 100459: https://golang.org/cl/100459: cmd/compile: reject type switch with guarded declaration and no cases -->
<!-- CL 106797: https://golang.org/cl/106797: cmd/compile: enable indexed export format by default -->
<!-- CL 108475: https://golang.org/cl/108475: cmd/compile: add softfloat support to mips64{,le} -->
<!-- CL 97375: https://golang.org/cl/97375: cmd/compile, cmd/compile/internal/syntax: print relative column info -->
<!-- CL 110395: https://golang.org/cl/110395: cmd/go, cmd/compile: use Windows response files to avoid arg length limits -->
<!-- CL 107475: https://golang.org/cl/107475: cmd/internal/obj/arm, runtime: delete old ARM softfloat code -->
<!-- CL 112436: https://golang.org/cl/112436: cmd/pprof: add readline support similar to upstream -->
<dl id="all"><dt><a href="/pkg/all/">all</a></dt>
  <dd>
    <p><!-- CL 93875 -->
      TODO: <a href="https://golang.org/cl/93875">https://golang.org/cl/93875</a>: enable c-shared/c-archive support for freebsd/amd64
    </p>

    <p><!-- CL 94255 -->
      TODO: <a href="https://golang.org/cl/94255">https://golang.org/cl/94255</a>: drop support for Windows Vista or below (Windows XP)
    </p>

    <p><!-- CL 115038 -->
      TODO: <a href="https://golang.org/cl/115038">https://golang.org/cl/115038</a>: remove support for macOS 10.9 and earlier
    </p>

</dl><!-- all -->

<dl id="crypto"><dt><a href="/pkg/crypto/">crypto</a></dt>
  <dd>
    <p><!-- CL 64451 -->
      TODO: <a href="https://golang.org/cl/64451">https://golang.org/cl/64451</a>: randomly read an extra byte of randomness in some places.
    </p>

</dl><!-- crypto -->

<dl id="crypto/cipher"><dt><a href="/pkg/crypto/cipher/">crypto/cipher</a></dt>
  <dd>
    <p><!-- CL 48510, CL 116435 -->
      TODO: <a href="https://golang.org/cl/48510">https://golang.org/cl/48510</a>: add NewGCMWithTagSize for custom tag sizes.
    </p>

</dl><!-- crypto/cipher -->

<dl id="crypto/rsa"><dt><a href="/pkg/crypto/rsa/">crypto/rsa</a></dt>
  <dd>
    <p><!-- CL 103876 -->
      TODO: <a href="https://golang.org/cl/103876">https://golang.org/cl/103876</a>: add PublicKey.Size accessor
    </p>

</dl><!-- crypto/rsa -->

<dl id="debug/elf"><dt><a href="/pkg/debug/elf/">debug/elf</a></dt>
  <dd>
    <p><!-- CL 112115 -->
      TODO: <a href="https://golang.org/cl/112115">https://golang.org/cl/112115</a>: add machine and OSABI constants
    </p>

</dl><!-- debug/elf -->

<dl id="encoding/asn1"><dt><a href="/pkg/encoding/asn1/">encoding/asn1</a></dt>
  <dd>
    <p><!-- CL 110561 -->
      TODO: <a href="https://golang.org/cl/110561">https://golang.org/cl/110561</a>: allow Marshaling and Unmarshaling private tag class
    </p>

</dl><!-- encoding/asn1 -->

<dl id="encoding/base32"><dt><a href="/pkg/encoding/base32/">encoding/base32</a></dt>
  <dd>
    <p><!-- CL 112516 -->
      TODO: <a href="https://golang.org/cl/112516">https://golang.org/cl/112516</a>: handle surplus padding consistently
    </p>

</dl><!-- encoding/base32 -->

<dl id="encoding/csv"><dt><a href="/pkg/encoding/csv/">encoding/csv</a></dt>
  <dd>
    <p><!-- CL 99696 -->
      TODO: <a href="https://golang.org/cl/99696">https://golang.org/cl/99696</a>: disallow quote for use as Comma
    </p>

</dl><!-- encoding/csv -->

<dl id="go/build, runtime/internal/sys"><dt><a href="/pkg/go/build, runtime/internal/sys/">go/build, runtime/internal/sys</a></dt>
  <dd>
    <p><!-- CL 106256 -->
      TODO: <a href="https://golang.org/cl/106256">https://golang.org/cl/106256</a>: reserve RISC-V arch names
    </p>

</dl><!-- go/build, runtime/internal/sys -->

<dl id="image/gif"><dt><a href="/pkg/image/gif/">image/gif</a></dt>
  <dd>
    <p><!-- CL 93076 -->
      TODO: <a href="https://golang.org/cl/93076">https://golang.org/cl/93076</a>: support non-looping animated gifs (LoopCount=-1)
    </p>

</dl><!-- image/gif -->

<dl id="io/ioutil"><dt><a href="/pkg/io/ioutil/">io/ioutil</a></dt>
  <dd>
    <p><!-- CL 105675 -->
      TODO: <a href="https://golang.org/cl/105675">https://golang.org/cl/105675</a>: change TempFile prefix to a pattern
    </p>

</dl><!-- io/ioutil -->

<dl id="math/big"><dt><a href="/pkg/math/big/">math/big</a></dt>
  <dd>
    <p><!-- CL 74851 -->
      TODO: <a href="https://golang.org/cl/74851">https://golang.org/cl/74851</a>: speed-up addMulVVW on amd64
    </p>

</dl><!-- math/big -->

<dl id="net"><dt><a href="/pkg/net/">net</a></dt>
  <dd>
    <p><!-- CL 72810 -->
      TODO: <a href="https://golang.org/cl/72810">https://golang.org/cl/72810</a>: add ListenConfig, Dialer.Control to permit socket opts before listen/dial
    </p>

    <p><!-- CL 76391 -->
      TODO: <a href="https://golang.org/cl/76391">https://golang.org/cl/76391</a>: implement (*syscall.RawConn).Read/Write on Windows
    </p>

    <p><!-- CL 107715 -->
      TODO: <a href="https://golang.org/cl/107715">https://golang.org/cl/107715</a>: add support for splice(2) in (*TCPConn).ReadFrom on Linux
    </p>

    <p><!-- CL 108297 -->
      TODO: <a href="https://golang.org/cl/108297">https://golang.org/cl/108297</a>: calling File leaves the socket in nonblocking mode
    </p>

</dl><!-- net -->

<dl id="net/http"><dt><a href="/pkg/net/http/">net/http</a></dt>
  <dd>
    <p><!-- CL 89275 -->
      TODO: <a href="https://golang.org/cl/89275">https://golang.org/cl/89275</a>: don&#39;t sniff Content-type in Server when X-Content-Type-Options:nosniff
    </p>

    <p><!-- CL 93296 -->
      TODO: <a href="https://golang.org/cl/93296">https://golang.org/cl/93296</a>: add StatusMisdirectedRequest (421)
    </p>

</dl><!-- net/http -->

<dl id="os"><dt><a href="/pkg/os/">os</a></dt>
  <dd>
    <p><!-- CL 78835 -->
      TODO: <a href="https://golang.org/cl/78835">https://golang.org/cl/78835</a>: add UserCacheDir
    </p>

    <p><!-- CL 94856 -->
      TODO: <a href="https://golang.org/cl/94856">https://golang.org/cl/94856</a>: add ModeIrregular flag
    </p>

    <p><!-- CL 99337 -->
      TODO: <a href="https://golang.org/cl/99337">https://golang.org/cl/99337</a>: enable symlink creation on Windows 10
    </p>

    <p><!-- CL 100077 -->
      TODO: <a href="https://golang.org/cl/100077">https://golang.org/cl/100077</a>: use poller when NewFile is called with a blocking descriptor.
    </p>

</dl><!-- os -->

<dl id="os/signal"><dt><a href="/pkg/os/signal/">os/signal</a></dt>
  <dd>
    <p><!-- CL 108376 -->
      TODO: <a href="https://golang.org/cl/108376">https://golang.org/cl/108376</a>: add func Ignored(sig Signal) bool
    </p>

</dl><!-- os/signal -->

<dl id="os/user"><dt><a href="/pkg/os/user/">os/user</a></dt>
  <dd>
    <p><!-- CL 92456 -->
      TODO: <a href="https://golang.org/cl/92456">https://golang.org/cl/92456</a>: add a way to enforce pure Go implementation
    </p>

</dl><!-- os/user -->

<dl id="runtime"><dt><a href="/pkg/runtime/">runtime</a></dt>
  <dd>
    <p><!-- CL 85887 -->
      TODO: <a href="https://golang.org/cl/85887">https://golang.org/cl/85887</a>: use sparse mappings for the heap
    </p>

    <p><!-- CL 94076 -->
      TODO: <a href="https://golang.org/cl/94076">https://golang.org/cl/94076</a>: use native CAS and memory barrier on ARMv7
    </p>

    <p><!-- CL 106156 -->
      TODO: <a href="https://golang.org/cl/106156">https://golang.org/cl/106156</a>: use fixed TLS offsets on darwin/amd64 and darwin/386
    </p>

    <p><!-- CL 109255 -->
      TODO: <a href="https://golang.org/cl/109255">https://golang.org/cl/109255</a>: enable memory sanitizer on arm64
    </p>

</dl><!-- runtime -->

<dl id="runtime,cmd/ld"><dt><a href="/pkg/runtime,cmd/ld/">runtime,cmd/ld</a></dt>
  <dd>
    <p><!-- CL 108679 -->
      TODO: <a href="https://golang.org/cl/108679">https://golang.org/cl/108679</a>: on darwin, create theads using libc
    </p>

</dl><!-- runtime,cmd/ld -->

<dl id="runtime/pprof"><dt><a href="/pkg/runtime/pprof/">runtime/pprof</a></dt>
  <dd>
    <p><!-- CL 102696 -->
      TODO: <a href="https://golang.org/cl/102696">https://golang.org/cl/102696</a>: introduce &#34;allocs&#34; profile
    </p>

</dl><!-- runtime/pprof -->

<dl id="runtime/traceback"><dt><a href="/pkg/runtime/traceback/">runtime/traceback</a></dt>
  <dd>
    <p><!-- CL 70993 -->
      TODO: <a href="https://golang.org/cl/70993">https://golang.org/cl/70993</a>: support tracking goroutine ancestor tracebacks with GODEBUG=&#34;tracebackancestors=N&#34;
    </p>

</dl><!-- runtime/traceback -->

<dl id="sync"><dt><a href="/pkg/sync/">sync</a></dt>
  <dd>
    <p><!-- CL 87095 -->
      TODO: <a href="https://golang.org/cl/87095">https://golang.org/cl/87095</a>: enable profiling of RWMutex
    </p>

</dl><!-- sync -->

<dl id="syscall"><dt><a href="/pkg/syscall/">syscall</a></dt>
  <dd>
    <p><!-- CL 106275 -->
      TODO: <a href="https://golang.org/cl/106275">https://golang.org/cl/106275</a>: introduce Pointer type and use it instead of uintptr
    </p>

</dl><!-- syscall -->

<dl id="text/scanner"><dt><a href="/pkg/text/scanner/">text/scanner</a></dt>
  <dd>
    <p><!-- CL 112037 -->
      TODO: <a href="https://golang.org/cl/112037">https://golang.org/cl/112037</a>: return RawString token rather than String for raw string literals
    </p>

</dl><!-- text/scanner -->

<dl id="text/template"><dt><a href="/pkg/text/template/">text/template</a></dt>
  <dd>
    <p><!-- CL 84480 -->
      TODO: <a href="https://golang.org/cl/84480">https://golang.org/cl/84480</a>: add variable assignments
    </p>

</dl><!-- text/template -->

<dl id="time"><dt><a href="/pkg/time/">time</a></dt>
  <dd>
    <p><!-- CL 98157 -->
      TODO: <a href="https://golang.org/cl/98157">https://golang.org/cl/98157</a>: add support for parsing timezones denoted by sign and offset
    </p>

</dl><!-- time -->