mirror of
https://github.com/golang/go
synced 2024-09-04 23:44:16 +00:00
![Daniel Martí](/assets/img/avatar_default.png)
install.html still insisted that GOROOT must be set if a binary install of Go is set up in a custom directory. However, since 1.10, this has been unnecessary as the GOROOT will be found based on the location of the 'go' binary being run. Likewise, install-source.html includes an 'export GOROOT' line in a section that only talks about explicitly setting GOARCH and GOOS, which is optional. We don't want to have users think it is recommended to set GOROOT here either, so remove the unnecessary line. Change-Id: I7dfef09f9a1d003e0253b793d63ea40d5cf1837f Reviewed-on: https://go-review.googlesource.com/c/161758 Reviewed-by: Andrew Bonventre <andybons@golang.org> Reviewed-by: Ian Lance Taylor <iant@golang.org> Run-TryBot: Daniel Martí <mvdan@mvdan.cc> TryBot-Result: Gobot Gobot <gobot@golang.org>
677 lines
19 KiB
HTML
677 lines
19 KiB
HTML
<!--{
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"Title": "Installing Go from source",
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"Path": "/doc/install/source"
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}-->
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<h2 id="introduction">Introduction</h2>
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<p>
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Go is an open source project, distributed under a
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<a href="/LICENSE">BSD-style license</a>.
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This document explains how to check out the sources,
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build them on your own machine, and run them.
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</p>
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<p>
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Most users don't need to do this, and will instead install
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from precompiled binary packages as described in
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<a href="/doc/install">Getting Started</a>,
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a much simpler process.
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If you want to help develop what goes into those precompiled
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packages, though, read on.
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</p>
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<div class="detail">
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<p>
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There are two official Go compiler toolchains.
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This document focuses on the <code>gc</code> Go
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compiler and tools.
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For information on how to work on <code>gccgo</code>, a more traditional
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compiler using the GCC back end, see
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<a href="/doc/install/gccgo">Setting up and using gccgo</a>.
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</p>
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<p>
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The Go compilers support eight instruction sets.
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There are important differences in the quality of the compilers for the different
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architectures.
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</p>
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<dl>
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<dt>
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<code>amd64</code> (also known as <code>x86-64</code>)
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</dt>
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<dd>
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A mature implementation.
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</dd>
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<dt>
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<code>386</code> (<code>x86</code> or <code>x86-32</code>)
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</dt>
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<dd>
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Comparable to the <code>amd64</code> port.
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</dd>
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<dt>
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<code>arm</code> (<code>ARM</code>)
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</dt>
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<dd>
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Supports Linux, FreeBSD, NetBSD, OpenBSD and Darwin binaries. Less widely used than the other ports.
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</dd>
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<dt>
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<code>arm64</code> (<code>AArch64</code>)
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</dt>
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<dd>
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Supports Linux and Darwin binaries. New in 1.5 and not as well exercised as other ports.
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</dd>
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<dt>
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<code>ppc64, ppc64le</code> (64-bit PowerPC big- and little-endian)
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</dt>
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<dd>
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Supports Linux binaries. New in 1.5 and not as well exercised as other ports.
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</dd>
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<dt>
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<code>mips, mipsle</code> (32-bit MIPS big- and little-endian)
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</dt>
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<dd>
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Supports Linux binaries. New in 1.8 and not as well exercised as other ports.
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</dd>
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<dt>
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<code>mips64, mips64le</code> (64-bit MIPS big- and little-endian)
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</dt>
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<dd>
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Supports Linux binaries. New in 1.6 and not as well exercised as other ports.
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</dd>
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<dt>
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<code>s390x</code> (IBM System z)
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</dt>
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<dd>
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Supports Linux binaries. New in 1.7 and not as well exercised as other ports.
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</dd>
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</dl>
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<p>
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Except for things like low-level operating system interface code, the run-time
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support is the same in all ports and includes a mark-and-sweep garbage
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collector, efficient array and string slicing, and support for efficient
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goroutines, such as stacks that grow and shrink on demand.
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</p>
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<p>
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The compilers can target the DragonFly BSD, FreeBSD, Linux, NetBSD, OpenBSD,
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macOS (Darwin), Plan 9, Solaris and Windows operating systems.
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The full set of supported combinations is listed in the discussion of
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<a href="#environment">environment variables</a> below.
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</p>
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<p>
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See the main installation page for the <a href="/doc/install#requirements">overall system requirements</a>.
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The following additional constraints apply to systems that can be built only from source:
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</p>
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<ul>
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<li>For Linux on PowerPC 64-bit, the minimum supported kernel version is 2.6.37, meaning that
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Go does not support CentOS 6 on these systems.
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</li>
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</ul>
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</div>
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<h2 id="go14">Install Go compiler binaries</h2>
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<p>
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The Go toolchain is written in Go. To build it, you need a Go compiler installed.
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The scripts that do the initial build of the tools look for an existing Go tool
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chain in <code>$GOROOT_BOOTSTRAP</code>.
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If unset, the default value of <code>GOROOT_BOOTSTRAP</code>
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is <code>$HOME/go1.4</code>.
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</p>
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<p>
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There are many options for the bootstrap toolchain.
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After obtaining one, set <code>GOROOT_BOOTSTRAP</code> to the
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directory containing the unpacked tree.
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For example, <code>$GOROOT_BOOTSTRAP/bin/go</code> should be
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the <code>go</code> command binary for the bootstrap toolchain.
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</p>
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<p>
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To use a binary release as a bootstrap toolchain, see
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<a href="/dl/">the downloads page</a> or use any other
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packaged Go distribution.
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</p>
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<p>
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To build a bootstrap toolchain from source, use
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either the git branch <code>release-branch.go1.4</code> or
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<a href="https://dl.google.com/go/go1.4-bootstrap-20171003.tar.gz">go1.4-bootstrap-20171003.tar.gz</a>,
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which contains the Go 1.4 source code plus accumulated fixes
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to keep the tools running on newer operating systems.
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(Go 1.4 was the last distribution in which the toolchain was written in C.)
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After unpacking the Go 1.4 source, <code>cd</code> to
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the <code>src</code> subdirectory, set <code>CGO_ENABLED=0</code> in
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the environment, and run <code>make.bash</code> (or,
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on Windows, <code>make.bat</code>).
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</p>
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<p>
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To cross-compile a bootstrap toolchain from source, which is
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necessary on systems Go 1.4 did not target (for
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example, <code>linux/ppc64le</code>), install Go on a different system
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and run <a href="/src/bootstrap.bash">bootstrap.bash</a>.
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</p>
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<p>
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When run as (for example)
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</p>
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<pre>
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$ GOOS=linux GOARCH=ppc64 ./bootstrap.bash
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</pre>
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<p>
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<code>bootstrap.bash</code> cross-compiles a toolchain for that <code>GOOS/GOARCH</code>
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combination, leaving the resulting tree in <code>../../go-${GOOS}-${GOARCH}-bootstrap</code>.
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That tree can be copied to a machine of the given target type
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and used as <code>GOROOT_BOOTSTRAP</code> to bootstrap a local build.
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</p>
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<p>
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To use gccgo as the bootstrap toolchain, you need to arrange
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for <code>$GOROOT_BOOTSTRAP/bin/go</code> to be the go tool that comes
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as part of gccgo 5. For example on Ubuntu Vivid:
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</p>
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<pre>
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$ sudo apt-get install gccgo-5
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$ sudo update-alternatives --set go /usr/bin/go-5
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$ GOROOT_BOOTSTRAP=/usr ./make.bash
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</pre>
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<h2 id="git">Install Git, if needed</h2>
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<p>
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To perform the next step you must have Git installed. (Check that you
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have a <code>git</code> command before proceeding.)
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</p>
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<p>
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If you do not have a working Git installation,
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follow the instructions on the
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<a href="https://git-scm.com/downloads">Git downloads</a> page.
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</p>
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<h2 id="ccompiler">(Optional) Install a C compiler</h2>
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<p>
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To build a Go installation
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with <code><a href="/cmd/cgo">cgo</a></code> support, which permits Go
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programs to import C libraries, a C compiler such as <code>gcc</code>
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or <code>clang</code> must be installed first. Do this using whatever
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installation method is standard on the system.
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</p>
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<p>
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To build without <code>cgo</code>, set the environment variable
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<code>CGO_ENABLED=0</code> before running <code>all.bash</code> or
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<code>make.bash</code>.
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</p>
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<h2 id="fetch">Fetch the repository</h2>
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<p>Go will install to a directory named <code>go</code>.
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Change to the directory that will be its parent
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and make sure the <code>go</code> directory does not exist.
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Then clone the repository and check out the latest release tag
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(<code class="versionTag">go1.9</code>, for example):</p>
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<pre>
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$ git clone https://go.googlesource.com/go
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$ cd go
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$ git checkout <span class="versionTag"><i><tag></i></span>
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</pre>
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<p class="whereTag">
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Where <code><tag></code> is the version string of the release.
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</p>
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<h2 id="head">(Optional) Switch to the master branch</h2>
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<p>If you intend to modify the go source code, and
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<a href="/doc/contribute.html">contribute your changes</a>
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to the project, then move your repository
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off the release branch, and onto the master (development) branch.
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Otherwise, skip this step.</p>
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<pre>
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$ git checkout master
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</pre>
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<h2 id="install">Install Go</h2>
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<p>
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To build the Go distribution, run
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</p>
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<pre>
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$ cd src
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$ ./all.bash
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</pre>
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<p>
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(To build under Windows use <code>all.bat</code>.)
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</p>
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<p>
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If all goes well, it will finish by printing output like:
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</p>
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<pre>
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ALL TESTS PASSED
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---
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Installed Go for linux/amd64 in /home/you/go.
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Installed commands in /home/you/go/bin.
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*** You need to add /home/you/go/bin to your $PATH. ***
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</pre>
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<p>
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where the details on the last few lines reflect the operating system,
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architecture, and root directory used during the install.
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</p>
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<div class="detail">
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<p>
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For more information about ways to control the build, see the discussion of
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<a href="#environment">environment variables</a> below.
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<code>all.bash</code> (or <code>all.bat</code>) runs important tests for Go,
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which can take more time than simply building Go. If you do not want to run
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the test suite use <code>make.bash</code> (or <code>make.bat</code>)
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instead.
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</p>
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</div>
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<h2 id="testing">Testing your installation</h2>
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<p>
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Check that Go is installed correctly by building a simple program.
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</p>
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<p>
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Create a file named <code>hello.go</code> and put the following program in it:
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</p>
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<pre>
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package main
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import "fmt"
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func main() {
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fmt.Printf("hello, world\n")
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}
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</pre>
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<p>
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Then run it with the <code>go</code> tool:
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</p>
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<pre>
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$ go run hello.go
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hello, world
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</pre>
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<p>
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If you see the "hello, world" message then Go is installed correctly.
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</p>
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<h2 id="gopath">Set up your work environment</h2>
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<p>
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You're almost done.
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You just need to do a little more setup.
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</p>
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<p>
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<a href="/doc/code.html" class="download" id="start">
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<span class="big">How to Write Go Code</span>
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<span class="desc">Learn how to set up and use the Go tools</span>
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</a>
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</p>
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<p>
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The <a href="/doc/code.html">How to Write Go Code</a> document
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provides <b>essential setup instructions</b> for using the Go tools.
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</p>
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<h2 id="tools">Install additional tools</h2>
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<p>
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The source code for several Go tools (including <a href="/cmd/godoc/">godoc</a>)
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is kept in <a href="https://golang.org/x/tools">the go.tools repository</a>.
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To install all of them, run the <code>go</code> <code>get</code> command:
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</p>
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<pre>
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$ go get golang.org/x/tools/cmd/...
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</pre>
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<p>
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Or if you just want to install a specific command (<code>godoc</code> in this case):
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</p>
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<pre>
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$ go get golang.org/x/tools/cmd/godoc
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</pre>
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<p>
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To install these tools, the <code>go</code> <code>get</code> command requires
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that <a href="#git">Git</a> be installed locally.
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</p>
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<p>
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You must also have a workspace (<code>GOPATH</code>) set up;
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see <a href="/doc/code.html">How to Write Go Code</a> for the details.
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</p>
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<p>
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<b>Note</b>: The <code>go</code> command will install the <code>godoc</code>
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binary to <code>$GOROOT/bin</code> (or <code>$GOBIN</code>) and the
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<code>cover</code> and <code>vet</code> binaries to
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<code>$GOROOT/pkg/tool/$GOOS_$GOARCH</code>.
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You can access the latter commands with
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"<code>go</code> <code>tool</code> <code>cover</code>" and
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"<code>go</code> <code>tool</code> <code>vet</code>".
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</p>
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<h2 id="community">Community resources</h2>
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<p>
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The usual community resources such as
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<code>#go-nuts</code> on the <a href="https://freenode.net/">Freenode</a> IRC server
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and the
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<a href="//groups.google.com/group/golang-nuts">Go Nuts</a>
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mailing list have active developers that can help you with problems
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with your installation or your development work.
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For those who wish to keep up to date,
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there is another mailing list, <a href="//groups.google.com/group/golang-checkins">golang-checkins</a>,
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that receives a message summarizing each checkin to the Go repository.
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</p>
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<p>
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Bugs can be reported using the <a href="//golang.org/issue/new">Go issue tracker</a>.
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</p>
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<h2 id="releases">Keeping up with releases</h2>
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<p>
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New releases are announced on the
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<a href="//groups.google.com/group/golang-announce">golang-announce</a>
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mailing list.
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Each announcement mentions the latest release tag, for instance,
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<code class="versionTag">go1.9</code>.
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</p>
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<p>
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To update an existing tree to the latest release, you can run:
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</p>
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<pre>
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$ cd go/src
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$ git fetch
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$ git checkout <span class="versionTag"><i><tag></i></psan>
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$ ./all.bash
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</pre>
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|
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<p class="whereTag">
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Where <code><tag></code> is the version string of the release.
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</p>
|
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|
|
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<h2 id="environment">Optional environment variables</h2>
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<p>
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The Go compilation environment can be customized by environment variables.
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<i>None is required by the build</i>, but you may wish to set some
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to override the defaults.
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</p>
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<ul>
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<li><code>$GOROOT</code>
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<p>
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The root of the Go tree, often <code>$HOME/go1.X</code>.
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Its value is built into the tree when it is compiled, and
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defaults to the parent of the directory where <code>all.bash</code> was run.
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There is no need to set this unless you want to switch between multiple
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local copies of the repository.
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</p>
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</li>
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<li><code>$GOROOT_FINAL</code>
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<p>
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The value assumed by installed binaries and scripts when
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<code>$GOROOT</code> is not set explicitly.
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It defaults to the value of <code>$GOROOT</code>.
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If you want to build the Go tree in one location
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but move it elsewhere after the build, set
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<code>$GOROOT_FINAL</code> to the eventual location.
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</p>
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</li>
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<li><code>$GOOS</code> and <code>$GOARCH</code>
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<p>
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The name of the target operating system and compilation architecture.
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These default to the values of <code>$GOHOSTOS</code> and
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<code>$GOHOSTARCH</code> respectively (described below).
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</li>
|
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<p>
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|
Choices for <code>$GOOS</code> are
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<code>darwin</code> (macOS 10.10 and above and iOS), <code>dragonfly</code>, <code>freebsd</code>,
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<code>linux</code>, <code>netbsd</code>, <code>openbsd</code>,
|
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<code>plan9</code>, <code>solaris</code> and <code>windows</code>.
|
|
Choices for <code>$GOARCH</code> are
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<code>amd64</code> (64-bit x86, the most mature port),
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<code>386</code> (32-bit x86), <code>arm</code> (32-bit ARM), <code>arm64</code> (64-bit ARM),
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<code>ppc64le</code> (PowerPC 64-bit, little-endian), <code>ppc64</code> (PowerPC 64-bit, big-endian),
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<code>mips64le</code> (MIPS 64-bit, little-endian), <code>mips64</code> (MIPS 64-bit, big-endian),
|
|
<code>mipsle</code> (MIPS 32-bit, little-endian), <code>mips</code> (MIPS 32-bit, big-endian), and
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<code>s390x</code> (IBM System z 64-bit, big-endian).
|
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The valid combinations of <code>$GOOS</code> and <code>$GOARCH</code> are:
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<table cellpadding="0">
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<tr>
|
|
<th width="50"></th><th align="left" width="100"><code>$GOOS</code></th> <th align="left" width="100"><code>$GOARCH</code></th>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>android</code></td> <td><code>arm</code></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>darwin</code></td> <td><code>386</code></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>darwin</code></td> <td><code>amd64</code></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>darwin</code></td> <td><code>arm</code></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>darwin</code></td> <td><code>arm64</code></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>dragonfly</code></td> <td><code>amd64</code></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>freebsd</code></td> <td><code>386</code></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>freebsd</code></td> <td><code>amd64</code></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>freebsd</code></td> <td><code>arm</code></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>linux</code></td> <td><code>386</code></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>linux</code></td> <td><code>amd64</code></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>linux</code></td> <td><code>arm</code></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>linux</code></td> <td><code>arm64</code></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>linux</code></td> <td><code>ppc64</code></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>linux</code></td> <td><code>ppc64le</code></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>linux</code></td> <td><code>mips</code></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>linux</code></td> <td><code>mipsle</code></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>linux</code></td> <td><code>mips64</code></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>linux</code></td> <td><code>mips64le</code></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>linux</code></td> <td><code>s390x</code></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>netbsd</code></td> <td><code>386</code></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>netbsd</code></td> <td><code>amd64</code></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>netbsd</code></td> <td><code>arm</code></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>openbsd</code></td> <td><code>386</code></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>openbsd</code></td> <td><code>amd64</code></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>openbsd</code></td> <td><code>arm</code></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>plan9</code></td> <td><code>386</code></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>plan9</code></td> <td><code>amd64</code></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>solaris</code></td> <td><code>amd64</code></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>windows</code></td> <td><code>386</code></td>
|
|
</tr>
|
|
<tr>
|
|
<td></td><td><code>windows</code></td> <td><code>amd64</code></td>
|
|
</tr>
|
|
</table>
|
|
<br>
|
|
|
|
<li><code>$GOHOSTOS</code> and <code>$GOHOSTARCH</code>
|
|
<p>
|
|
The name of the host operating system and compilation architecture.
|
|
These default to the local system's operating system and
|
|
architecture.
|
|
</p>
|
|
</li>
|
|
|
|
<p>
|
|
Valid choices are the same as for <code>$GOOS</code> and
|
|
<code>$GOARCH</code>, listed above.
|
|
The specified values must be compatible with the local system.
|
|
For example, you should not set <code>$GOHOSTARCH</code> to
|
|
<code>arm</code> on an x86 system.
|
|
</p>
|
|
|
|
<li><code>$GOBIN</code>
|
|
<p>
|
|
The location where Go binaries will be installed.
|
|
The default is <code>$GOROOT/bin</code>.
|
|
After installing, you will want to arrange to add this
|
|
directory to your <code>$PATH</code>, so you can use the tools.
|
|
If <code>$GOBIN</code> is set, the <a href="/cmd/go">go command</a>
|
|
installs all commands there.
|
|
</p>
|
|
</li>
|
|
|
|
<li><code>$GO386</code> (for <code>386</code> only, default is auto-detected
|
|
if built on either <code>386</code> or <code>amd64</code>, <code>387</code> otherwise)
|
|
<p>
|
|
This controls the code generated by gc to use either the 387 floating-point unit
|
|
(set to <code>387</code>) or SSE2 instructions (set to <code>sse2</code>) for
|
|
floating point computations.
|
|
</p>
|
|
<ul>
|
|
<li><code>GO386=387</code>: use x87 for floating point operations; should support all x86 chips (Pentium MMX or later).</li>
|
|
<li><code>GO386=sse2</code>: use SSE2 for floating point operations; has better performance than 387, but only available on Pentium 4/Opteron/Athlon 64 or later.</li>
|
|
</ul>
|
|
</li>
|
|
|
|
<li><code>$GOARM</code> (for <code>arm</code> only; default is auto-detected if building
|
|
on the target processor, 6 if not)
|
|
<p>
|
|
This sets the ARM floating point co-processor architecture version the run-time
|
|
should target. If you are compiling on the target system, its value will be auto-detected.
|
|
</p>
|
|
<ul>
|
|
<li><code>GOARM=5</code>: use software floating point; when CPU doesn't have VFP co-processor</li>
|
|
<li><code>GOARM=6</code>: use VFPv1 only; default if cross compiling; usually ARM11 or better cores (VFPv2 or better is also supported)</li>
|
|
<li><code>GOARM=7</code>: use VFPv3; usually Cortex-A cores</li>
|
|
</ul>
|
|
<p>
|
|
If in doubt, leave this variable unset, and adjust it if required
|
|
when you first run the Go executable.
|
|
The <a href="//golang.org/wiki/GoArm">GoARM</a> page
|
|
on the <a href="//golang.org/wiki">Go community wiki</a>
|
|
contains further details regarding Go's ARM support.
|
|
</p>
|
|
</li>
|
|
|
|
<li><code>$GOMIPS</code> (for <code>mips</code> and <code>mipsle</code> only) <br> <code>$GOMIPS64</code> (for <code>mips64</code> and <code>mips64le</code> only)
|
|
<p>
|
|
These variables set whether to use floating point instructions. Set to "<code>hardfloat</code>" to use floating point instructions; this is the default. Set to "<code>softfloat</code>" to use soft floating point.
|
|
</p>
|
|
</li>
|
|
|
|
</ul>
|
|
|
|
<p>
|
|
Note that <code>$GOARCH</code> and <code>$GOOS</code> identify the
|
|
<em>target</em> environment, not the environment you are running on.
|
|
In effect, you are always cross-compiling.
|
|
By architecture, we mean the kind of binaries
|
|
that the target environment can run:
|
|
an x86-64 system running a 32-bit-only operating system
|
|
must set <code>GOARCH</code> to <code>386</code>,
|
|
not <code>amd64</code>.
|
|
</p>
|
|
|
|
<p>
|
|
If you choose to override the defaults,
|
|
set these variables in your shell profile (<code>$HOME/.bashrc</code>,
|
|
<code>$HOME/.profile</code>, or equivalent). The settings might look
|
|
something like this:
|
|
</p>
|
|
|
|
<pre>
|
|
export GOARCH=amd64
|
|
export GOOS=linux
|
|
</pre>
|
|
|
|
<p>
|
|
although, to reiterate, none of these variables needs to be set to build,
|
|
install, and develop the Go tree.
|
|
</p>
|