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diff --git a/_content/doc/install/source.html b/_content/doc/install/source.html new file mode 100644 index 00000000..e164825c --- /dev/null +++ b/_content/doc/install/source.html @@ -0,0 +1,781 @@ +<!--{ + "Title": "Installing Go from source" +}--> + +<p> +This topic describes how to build and run Go from source code. +To install with an installer, see <a href="/doc/install">Download and install</a>. +</p> + +<h2 id="introduction">Introduction</h2> + +<p> +Go is an open source project, distributed under a +<a href="/LICENSE">BSD-style license</a>. +This document explains how to check out the sources, +build them on your own machine, and run them. +</p> + +<p> +Most users don't need to do this, and will instead install +from precompiled binary packages as described in +<a href="/doc/install">Download and install</a>, +a much simpler process. +If you want to help develop what goes into those precompiled +packages, though, read on. +</p> + +<div class="detail"> + +<p> +There are two official Go compiler toolchains. +This document focuses on the <code>gc</code> Go +compiler and tools. +For information on how to work on <code>gccgo</code>, a more traditional +compiler using the GCC back end, see +<a href="/doc/install/gccgo">Setting up and using gccgo</a>. +</p> + +<p> +The Go compilers support the following instruction sets: + +<dl> +<dt> + <code>amd64</code>, <code>386</code> +</dt> +<dd> + The <code>x86</code> instruction set, 64- and 32-bit. +</dd> +<dt> + <code>arm64</code>, <code>arm</code> +</dt> +<dd> + The <code>ARM</code> instruction set, 64-bit (<code>AArch64</code>) and 32-bit. +</dd> +<dt> + <code>mips64</code>, <code>mips64le</code>, <code>mips</code>, <code>mipsle</code> +</dt> +<dd> + The <code>MIPS</code> instruction set, big- and little-endian, 64- and 32-bit. +</dd> +<dt> + <code>ppc64</code>, <code>ppc64le</code> +</dt> +<dd> + The 64-bit PowerPC instruction set, big- and little-endian. +</dd> +<dt> + <code>riscv64</code> +</dt> +<dd> + The 64-bit RISC-V instruction set. +</dd> +<dt> + <code>s390x</code> +</dt> +<dd> + The IBM z/Architecture. +</dd> +<dt> + <code>wasm</code> +</dt> +<dd> + <a href="https://webassembly.org">WebAssembly</a>. +</dd> +</dl> +</p> + +<p> +The compilers can target the AIX, Android, DragonFly BSD, FreeBSD, +Illumos, Linux, macOS/iOS (Darwin), NetBSD, OpenBSD, Plan 9, Solaris, +and Windows operating systems (although not all operating systems +support all architectures). +</p> + +<p> +A list of ports which are considered "first class" is available at the +<a href="/wiki/PortingPolicy#first-class-ports">first class ports</a> +wiki page. +</p> + +<p> +The full set of supported combinations is listed in the +discussion of <a href="#environment">environment variables</a> below. +</p> + +<p> +See the main installation page for the <a href="/doc/install#requirements">overall system requirements</a>. +The following additional constraints apply to systems that can be built only from source: +</p> + +<ul> +<li>For Linux on PowerPC 64-bit, the minimum supported kernel version is 2.6.37, meaning that +Go does not support CentOS 6 on these systems. +</li> +</ul> + +</div> + +<h2 id="go14">Install Go compiler binaries for bootstrap</h2> + +<p> +The Go toolchain is written in Go. To build it, you need a Go compiler installed. +The scripts that do the initial build of the tools look for a "go" command +in <code>$PATH</code>, so as long as you have Go installed in your +system and configured in your <code>$PATH</code>, you are ready to build Go +from source. +Or if you prefer you can set <code>$GOROOT_BOOTSTRAP</code> to the +root of a Go installation to use to build the new Go toolchain; +<code>$GOROOT_BOOTSTRAP/bin/go</code> should be the go command to use.</p> + +<p> +There are four possible ways to obtain a bootstrap toolchain: +</p> + +<ul> +<li>Download a recent binary release of Go. +<li>Cross-compile a toolchain using a system with a working Go installation. +<li>Use gccgo. +<li>Compile a toolchain from Go 1.4, the last Go release with a compiler written in C. +</ul> + +<p> +These approaches are detailed below. +</p> + +<h3 id="bootstrapFromBinaryRelease">Bootstrap toolchain from binary release</h3> + +<p> +To use a binary release as a bootstrap toolchain, see +<a href="/dl/">the downloads page</a> or use any other +packaged Go distribution. +</p> + +<h3 id="bootstrapFromCrosscompiledSource">Bootstrap toolchain from cross-compiled source</h3> + +<p> +To cross-compile a bootstrap toolchain from source, which is +necessary on systems Go 1.4 did not target (for +example, <code>linux/ppc64le</code>), install Go on a different system +and run <a href="/src/bootstrap.bash">bootstrap.bash</a>. +</p> + +<p> +When run as (for example) +</p> + +<pre> +$ GOOS=linux GOARCH=ppc64 ./bootstrap.bash +</pre> + +<p> +<code>bootstrap.bash</code> cross-compiles a toolchain for that <code>GOOS/GOARCH</code> +combination, leaving the resulting tree in <code>../../go-${GOOS}-${GOARCH}-bootstrap</code>. +That tree can be copied to a machine of the given target type +and used as <code>GOROOT_BOOTSTRAP</code> to bootstrap a local build. +</p> + +<h3 id="bootstrapFromGccgo">Bootstrap toolchain using gccgo</h3> + +<p> +To use gccgo as the bootstrap toolchain, you need to arrange +for <code>$GOROOT_BOOTSTRAP/bin/go</code> to be the go tool that comes +as part of gccgo 5. For example on Ubuntu Vivid: +</p> + +<pre> +$ sudo apt-get install gccgo-5 +$ sudo update-alternatives --set go /usr/bin/go-5 +$ GOROOT_BOOTSTRAP=/usr ./make.bash +</pre> + +<h3 id="bootstrapFromSource">Bootstrap toolchain from C source code</h3> + +<p> +To build a bootstrap toolchain from C source code, use +either the git branch <code>release-branch.go1.4</code> or +<a href="https://dl.google.com/go/go1.4-bootstrap-20171003.tar.gz">go1.4-bootstrap-20171003.tar.gz</a>, +which contains the Go 1.4 source code plus accumulated fixes +to keep the tools running on newer operating systems. +(Go 1.4 was the last distribution in which the toolchain was written in C.) +After unpacking the Go 1.4 source, <code>cd</code> to +the <code>src</code> subdirectory, set <code>CGO_ENABLED=0</code> in +the environment, and run <code>make.bash</code> (or, +on Windows, <code>make.bat</code>). +</p> + +<p> +Once the Go 1.4 source has been unpacked into your GOROOT_BOOTSTRAP directory, +you must keep this git clone instance checked out to branch +<code>release-branch.go1.4</code>. Specifically, do not attempt to reuse +this git clone in the later step named "Fetch the repository." The go1.4 +bootstrap toolchain <b>must be able</b> to properly traverse the go1.4 sources +that it assumes are present under this repository root. +</p> + +<p> +Note that Go 1.4 does not run on all systems that later versions of Go do. +In particular, Go 1.4 does not support current versions of macOS. +On such systems, the bootstrap toolchain must be obtained using one of the other methods. +</p> + +<h2 id="git">Install Git, if needed</h2> + +<p> +To perform the next step you must have Git installed. (Check that you +have a <code>git</code> command before proceeding.) +</p> + +<p> +If you do not have a working Git installation, +follow the instructions on the +<a href="https://git-scm.com/downloads">Git downloads</a> page. +</p> + +<h2 id="ccompiler">(Optional) Install a C compiler</h2> + +<p> +To build a Go installation +with <code><a href="/cmd/cgo">cgo</a></code> support, which permits Go +programs to import C libraries, a C compiler such as <code>gcc</code> +or <code>clang</code> must be installed first. Do this using whatever +installation method is standard on the system. +</p> + +<p> +To build without <code>cgo</code>, set the environment variable +<code>CGO_ENABLED=0</code> before running <code>all.bash</code> or +<code>make.bash</code>. +</p> + +<h2 id="fetch">Fetch the repository</h2> + +<p>Change to the directory where you intend to install Go, and make sure +the <code>goroot</code> directory does not exist. Then clone the repository +and check out the latest release tag (<code class="versionTag">go1.12</code>, +for example):</p> + +<pre> +$ git clone https://go.googlesource.com/go goroot +$ cd goroot +$ git checkout <span class="versionTag"><i><tag></i></span> +</pre> + +<p class="whereTag"> +Where <code><tag></code> is the version string of the release. +</p> + +<p>Go will be installed in the directory where it is checked out. For example, +if Go is checked out in <code>$HOME/goroot</code>, executables will be installed +in <code>$HOME/goroot/bin</code>. The directory may have any name, but note +that if Go is checked out in <code>$HOME/go</code>, it will conflict with +the default location of <code>$GOPATH</code>. +See <a href="#gopath"><code>GOPATH</code></a> below.</p> + +<p> +Reminder: If you opted to also compile the bootstrap binaries from source (in an +earlier section), you still need to <code>git clone</code> again at this point +(to checkout the latest <code><tag></code>), because you must keep your +go1.4 repository distinct. +</p> + +<h2 id="head">(Optional) Switch to the master branch</h2> + +<p>If you intend to modify the go source code, and +<a href="/doc/contribute.html">contribute your changes</a> +to the project, then move your repository +off the release tag, and onto the master (development) branch. +Otherwise, skip this step.</p> + +<pre> +$ git checkout master +</pre> + +<h2 id="install">Install Go</h2> + +<p> +To build the Go distribution, run +</p> + +<pre> +$ cd src +$ ./all.bash +</pre> + +<p> +(To build under Windows use <code>all.bat</code>.) +</p> + +<p> +If all goes well, it will finish by printing output like: +</p> + +<pre> +ALL TESTS PASSED + +--- +Installed Go for linux/amd64 in /home/you/go. +Installed commands in /home/you/go/bin. +*** You need to add /home/you/go/bin to your $PATH. *** +</pre> + +<p> +where the details on the last few lines reflect the operating system, +architecture, and root directory used during the install. +</p> + +<div class="detail"> +<p> +For more information about ways to control the build, see the discussion of +<a href="#environment">environment variables</a> below. +<code>all.bash</code> (or <code>all.bat</code>) runs important tests for Go, +which can take more time than simply building Go. If you do not want to run +the test suite use <code>make.bash</code> (or <code>make.bat</code>) +instead. +</p> +</div> + + +<h2 id="testing">Testing your installation</h2> + +<p> +Check that Go is installed correctly by building a simple program. +</p> + +<p> +Create a file named <code>hello.go</code> and put the following program in it: +</p> + +<pre> +package main + +import "fmt" + +func main() { + fmt.Printf("hello, world\n") +} +</pre> + +<p> +Then run it with the <code>go</code> tool: +</p> + +<pre> +$ go run hello.go +hello, world +</pre> + +<p> +If you see the "hello, world" message then Go is installed correctly. +</p> + +<h2 id="gopath">Set up your work environment</h2> + +<p> +You're almost done. +You just need to do a little more setup. +</p> + +<p> +<a href="/doc/code.html" class="download" id="start"> +<span class="big">How to Write Go Code</span> +<span class="desc">Learn how to set up and use the Go tools</span> +</a> +</p> + +<p> +The <a href="/doc/code.html">How to Write Go Code</a> document +provides <b>essential setup instructions</b> for using the Go tools. +</p> + + +<h2 id="tools">Install additional tools</h2> + +<p> +The source code for several Go tools (including <a href="/cmd/godoc/">godoc</a>) +is kept in <a href="https://golang.org/x/tools">the go.tools repository</a>. +To install one of the tools (<code>godoc</code> in this case): +</p> + +<pre> +$ go get golang.org/x/tools/cmd/godoc +</pre> + +<p> +To install these tools, the <code>go</code> <code>get</code> command requires +that <a href="#git">Git</a> be installed locally. +</p> + +<p> +You must also have a workspace (<code>GOPATH</code>) set up; +see <a href="/doc/code.html">How to Write Go Code</a> for the details. +</p> + +<h2 id="community">Community resources</h2> + +<p> +The usual community resources such as +<code>#go-nuts</code> on the <a href="https://freenode.net/">Freenode</a> IRC server +and the +<a href="//groups.google.com/group/golang-nuts">Go Nuts</a> +mailing list have active developers that can help you with problems +with your installation or your development work. +For those who wish to keep up to date, +there is another mailing list, <a href="//groups.google.com/group/golang-checkins">golang-checkins</a>, +that receives a message summarizing each checkin to the Go repository. +</p> + +<p> +Bugs can be reported using the <a href="//golang.org/issue/new">Go issue tracker</a>. +</p> + + +<h2 id="releases">Keeping up with releases</h2> + +<p> +New releases are announced on the +<a href="//groups.google.com/group/golang-announce">golang-announce</a> +mailing list. +Each announcement mentions the latest release tag, for instance, +<code class="versionTag">go1.9</code>. +</p> + +<p> +To update an existing tree to the latest release, you can run: +</p> + +<pre> +$ cd go/src +$ git fetch +$ git checkout <span class="versionTag"><i><tag></i></psan> +$ ./all.bash +</pre> + +<p class="whereTag"> +Where <code><tag></code> is the version string of the release. +</p> + + +<h2 id="environment">Optional environment variables</h2> + +<p> +The Go compilation environment can be customized by environment variables. +<i>None is required by the build</i>, but you may wish to set some +to override the defaults. +</p> + +<ul> +<li><code>$GOROOT</code> +<p> +The root of the Go tree, often <code>$HOME/go1.X</code>. +Its value is built into the tree when it is compiled, and +defaults to the parent of the directory where <code>all.bash</code> was run. +There is no need to set this unless you want to switch between multiple +local copies of the repository. +</p> +</li> + +<li><code>$GOROOT_FINAL</code> +<p> +The value assumed by installed binaries and scripts when +<code>$GOROOT</code> is not set explicitly. +It defaults to the value of <code>$GOROOT</code>. +If you want to build the Go tree in one location +but move it elsewhere after the build, set +<code>$GOROOT_FINAL</code> to the eventual location. +</p> +</li> + +<li id="gopath"><code>$GOPATH</code> +<p> +The directory where Go projects outside the Go distribution are typically +checked out. For example, <code>golang.org/x/tools</code> might be checked out +to <code>$GOPATH/src/golang.org/x/tools</code>. Executables outside the +Go distribution are installed in <code>$GOPATH/bin</code> (or +<code>$GOBIN</code>, if set). Modules are downloaded and cached in +<code>$GOPATH/pkg/mod</code>. +</p> + +<p>The default location of <code>$GOPATH</code> is <code>$HOME/go</code>, +and it's not usually necessary to set <code>GOPATH</code> explicitly. However, +if you have checked out the Go distribution to <code>$HOME/go</code>, +you must set <code>GOPATH</code> to another location to avoid conflicts. +</p> +</li> + +<li><code>$GOBIN</code> +<p> +The directory where executables outside the Go distribution are installed +using the <a href="/cmd/go">go command</a>. For example, +<code>go get golang.org/x/tools/cmd/godoc</code> downloads, builds, and +installs <code>$GOBIN/godoc</code>. By default, <code>$GOBIN</code> is +<code>$GOPATH/bin</code> (or <code>$HOME/go/bin</code> if <code>GOPATH</code> +is not set). After installing, you will want to add this directory to +your <code>$PATH</code> so you can use installed tools. +</p> + +<p> +Note that the Go distribution's executables are installed in +<code>$GOROOT/bin</code> (for executables invoked by people) or +<code>$GOTOOLDIR</code> (for executables invoked by the go command; +defaults to <code>$GOROOT/pkg/$GOOS_$GOARCH</code>) instead of +<code>$GOBIN</code>. +</p> +</li> + +<li><code>$GOOS</code> and <code>$GOARCH</code> +<p> +The name of the target operating system and compilation architecture. +These default to the values of <code>$GOHOSTOS</code> and +<code>$GOHOSTARCH</code> respectively (described below). +</li> + +<p> +Choices for <code>$GOOS</code> are +<code>android</code>, <code>darwin</code>, <code>dragonfly</code>, +<code>freebsd</code>, <code>illumos</code>, <code>ios</code>, <code>js</code>, +<code>linux</code>, <code>netbsd</code>, <code>openbsd</code>, +<code>plan9</code>, <code>solaris</code> and <code>windows</code>. +</p> + +<p> +Choices for <code>$GOARCH</code> are +<code>amd64</code> (64-bit x86, the most mature port), +<code>386</code> (32-bit x86), <code>arm</code> (32-bit ARM), <code>arm64</code> (64-bit ARM), +<code>ppc64le</code> (PowerPC 64-bit, little-endian), <code>ppc64</code> (PowerPC 64-bit, big-endian), +<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), +<code>s390x</code> (IBM System z 64-bit, big-endian), and +<code>wasm</code> (WebAssembly 32-bit). +</p> + +<p> +The valid combinations of <code>$GOOS</code> and <code>$GOARCH</code> are: +<table cellpadding="0"> +<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>aix</code></td> <td><code>ppc64</code></td> +</tr> +<tr> +<td></td><td><code>android</code></td> <td><code>386</code></td> +</tr> +<tr> +<td></td><td><code>android</code></td> <td><code>amd64</code></td> +</tr> +<tr> +<td></td><td><code>android</code></td> <td><code>arm</code></td> +</tr> +<tr> +<td></td><td><code>android</code></td> <td><code>arm64</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>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>illumos</code></td> <td><code>amd64</code></td> +</tr> +<tr> +<td></td><td><code>ios</code></td> <td><code>arm64</code></td> +</tr> +<tr> +<td></td><td><code>js</code></td> <td><code>wasm</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>riscv64</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>openbsd</code></td> <td><code>arm64</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>plan9</code></td> <td><code>arm</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>$GOHOSTARCH</code> to +<code>arm</code> on an x86 system. +</p> + +<li><code>$GO386</code> (for <code>386</code> only, defaults to <code>sse2</code>) +<p> +This variable controls how gc implements floating point computations. +</p> +<ul> + <li><code>GO386=softfloat</code>: use software 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 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>$GOMIPS64</code> (for <code>mips64</code> and <code>mips64le</code> only) +<p> + These variables set whether to use floating point instructions. Set to "<code>hardfloat</code>" to use floating point instructions; this is the default. Set to "<code>softfloat</code>" to use soft floating point. +</p> +</li> + +<li><code>$GOPPC64</code> (for <code>ppc64</code> and <code>ppc64le</code> only) +<p> +This variable sets the processor level (i.e. Instruction Set Architecture version) +for which the compiler will target. The default is <code>power8</code>. +</p> +<ul> + <li><code>GOPPC64=power8</code>: generate ISA v2.07 instructions</li> + <li><code>GOPPC64=power9</code>: generate ISA v3.00 instructions</li> +</ul> +</li> + + +<li><code>$GOWASM</code> (for <code>wasm</code> only) + <p> + This variable is a comma separated list of <a href="https://github.com/WebAssembly/proposals">experimental WebAssembly features</a> that the compiled WebAssembly binary is allowed to use. + The default is to use no experimental features. + </p> + <ul> + <li><code>GOWASM=satconv</code>: generate <a href="https://github.com/WebAssembly/nontrapping-float-to-int-conversions/blob/master/proposals/nontrapping-float-to-int-conversion/Overview.md">saturating (non-trapping) float-to-int conversions</a></li> + <li><code>GOWASM=signext</code>: generate <a href="https://github.com/WebAssembly/sign-extension-ops/blob/master/proposals/sign-extension-ops/Overview.md">sign-extension operators</a></li> + </ul> +</li> + +</ul> + +<p> +Note that <code>$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> |