Go

Go is an open source programming language supported by Google. From the Go documentation:

Go is expressive, concise, clean, and efficient. Its concurrency mechanisms make it easy to write programs that get the most out of multicore and networked machines, while its novel type system enables flexible and modular program construction. Go compiles quickly to machine code yet has the convenience of garbage collection and the power of run-time reflection. It's a fast, statically typed, compiled language that feels like a dynamically typed, interpreted language.

Installation

Install the go package, which includes the standard Go compiler and other development tools. See the go command documentation for a list of included subcommands.

Alternative Compilers

The go package includes the standard Go compiler, which is called gc. The following alternative compilers are also available.

gccgo

A frontend for GCC called gccgo is provided by the gcc-go package. gccgo may produce faster binaries than gc in some cases and can target additional operating systems and architectures. In practice, gc produces faster binaries than gccgo for almost all workloads.

TinyGo

TinyGo is an LLVM based compiler designed to produce very small binaries for embedded systems and WebAssembly. It is provided by the tinygo package.

Tools

The following packages provide developer tools for Go:

Go tools — Various tools and Go packages mostly for static analysis of Go programs.

https://cs.opensource.google/go/x/tools || go-tools

gopls — The official Go language server.

https://pkg.go.dev/golang.org/x/tools/gopls || gopls

Delve — A debugger for the Go programming language.

https://github.com/go-delve/delve || delve

GoReleaser — A release automation tool for Go projects.

https://goreleaser.com/ || goreleaser

gox — A tool for Go cross compilation that will parallelize builds for multiple platforms.

https://github.com/mitchellh/gox || gox

ko — A container image builder for Go applications.

https://github.com/ko-build/ko || ko

revive — A fast, configurable, extensible, flexible, and beautiful linter for Go.

https://revive.run/ || revive

Staticcheck — A state of the art linter for the Go programming language.

https://staticcheck.io/ || staticcheck

Yaegi — A Go interpreter. Includes the yaegi command-line interpreter/REPL.

https://github.com/traefik/yaegi || yaegi

Install directory

The go install command installs Go executables in the directory named by the GOBIN environment variable. GOBIN defaults to $GOPATH/bin, or ~/go/bin if the GOPATH environment variable is not set.

Tip: You can see all Go variables by running go env

For convenience, add the bin subdirectory to PATH:

$ export PATH="$PATH:$(go env GOBIN):$(go env GOPATH)/bin"

See How to Write Go Code and go help install for more information.

Tips and Tricks

Compiling source code

You can write a Hello World program as follows:

hello.go

package main

import "fmt"

func main() {
    fmt.Println("Hello, Arch!")
}

Then run it with the go tool:

$ go run hello.go

Hello, Arch!

Compilation with the standard compiler (same as go build -compiler=gc hello.go):

$ go build hello.go

Compilation with gccgo (same as go build -compiler=gccgo hello.go):

$ gccgo hello.go -o hello

Compilation with tinygo:

$ tinygo build -o hello ./hello.go

Cross compiling to other platforms

The standard compiler can natively cross-compile to a number of platforms. The procedure varies depending on whether the source code calls C code using cgo.

Without cgo

If cgo is not required for your build, then simply specify the target OS and architecture as environment variables to go build:

$ GOOS=linux GOARCH=arm64 go build .

See the official documentation for the valid combinations of GOOS and GOARCH.

With cgo

If cgo is required for your build, you have to provide the path to your C/C++ cross-compilers, via the CC/CXX environment variables.

Say you want to cross-compile for GOOS=linux and GOARCH=arm64.

You need first to install the aarch64-linux-gnu-gcc cross-compiler.

Here is a sample program that requires cgo, so that we can test the cross-compilation process:

hello.go

package main

// #include <stdio.h>
// void hello() { puts("Hello, Arch!"); }
import "C"

func main() {
    C.hello()
}

Then, you can cross-compile it like this:

$ GOOS=linux GOARCH=arm64 CGO_ENABLED=1 CC=/usr/bin/aarch64-linux-gnu-gcc go build hello.go

You can check that the architecture of the generated binary is actually aarch64:

$ file hello
hello: ELF 64-bit LSB executable, ARM aarch64, version 1 (SYSV), dynamically linked, interpreter /lib/ld-linux-aarch64.so.1, BuildID[sha1]=b1d92ae8840a019f36cc2aee4606b6ae4a581bf1, for GNU/Linux 3.7.0, not stripped

If you copy hello to a suitable host, you can test-run it:

[alarm@rpi3 ~]$ uname -a
Linux alarm 5.3.8-1-ARCH #1 SMP Tue Oct 29 19:31:23 MDT 2019 aarch64 GNU/Linux
[alarm@arpi3 ~]$ ./hello
Hello, Arch!

Using an alternate Go module mirror

By default, Go uses Google's service proxy.golang.org as a module mirror.

If an alternate mirror is desired, it can be changed with the environment variable GOPROXY, for example:

$ export GOPROXY=https://goproxy.io/

A number of public module mirrors are available, see for example: Go and Hugo Proxy Servers.

Troubleshooting

JetBrains Go Plugin

If you are using a JetBrains IDE and the Go plugin cannot find your Go SDK path, you might be using an incompatible package. Remove the gcc-go package and replace it with go. If your GOPATH is set, the IDE should now be able to find your Go SDK at /usr/lib/go.