Cross Compiling Golang

Mike Kusold / @mikekusold

Why?

• Code once, user everywhere
• Development speed
• Reduced infrastructure

Supported Platforms

$GOOS		$GOARCH
darwin		386
darwin		amd64
dragonfly	386
dragonfly	amd64
freebsd		386
freebsd		amd64
freebsd		arm
linux		386
linux		amd64
linux		arm
netbsd		386
netbsd		amd64
netbsd		arm
openbsd		386
openbsd		amd64
plan9		386
plan9		amd64
solaris		amd64
windows		386
windows		amd64
						

Setting up the toolchain

The hard way

Get the source code

						
git clone https://go.googlesource.com/go
cd go/
git checkout go1.4.2
cd src/
						
					

Build for your $GOHOSTOS

						
./all.bash
						
					

Build for each of your targets

						
# 64 bit OSX
GOOS=darwin GOARCH=amd64 CGO_ENABLED=1 ./make.bash
# 32 Bit Windows
GOOS=windows GOARCH=386 CGO_ENABLED=1 ./make.bash
# Raspberry Pi
GOOS=linux GOARCH=arm GOARM=5 CGO_ENABLED=1 ./make.bash
						
					

Verification

						
$ ls ../bin/
darwin_amd64  linux_arm  windows_386  go  gofmt
						
					

Sample Go App

						
package main

import (
	"fmt"
	"os/user"
)

func main() {
	// Get Current User
	currentUser, err := user.Current()
	if err != nil {
		fmt.Println("Error: " + err.Error())
	}

	fmt.Println("My home dir is: " + currentUser.HomeDir)
}
						
					

Building the app

						
go build sampleApp.go
GOOS="windows" GOARCH="386" ./go/bin/go build sampleApp.go
						
					

Demo

The Easy Way

gox

github.com/mitchellh/gox

Using gox

						
gox -build-toolchain
gox -osarch="darwin/amd64 linux/amd64 windows/amd64"
						
					

Thank you

@mikekusold