Cross compiled Go binaries are not suitable for production applications because code in the standard library relies on Cgo for DNS resolution with the native resolver, access to system certificate roots, and parts of os/user.
gonative is a simple tool which creates a build of Go that can cross compile to all platforms while still using the Cgo-enabled versions of the stdlib packages. It does this by downloading the binary distributions for each platform and copying their libraries into the proper places. It sets the correct mod time so they don't get rebuilt. It also copies some auto-generated runtime files into the build as well. gonative does not modify any Go that you have installed and builds a new installaion of Go in a separate directory (the current directory by default).
Once you have a toolchain for cross-compilation, you can use tools like gox to cross-compile native builds easily.
gonative will not help you if your own packages rely on Cgo
git clone https://github.com/inconshreveable/gonative cd gonative make
Alternatively, you can install gonative via
go get but the dependencies are not locked down.
go get github.com/inconshreveable/gonative
The 'build' command will build a toolchain in a directory called 'go' in your working directory.
To build a particular version of Go (default is 1.4):
gonative build -version=1.3.3
For options and help:
gonative build -h
How it works
gonative downloads the go source code and compiles it for your host platform. It then bootstraps the toolchain for all target platforms (but does not compile the standard library). Then, it fetches the official binary distributions for all target platforms and copies each pkg/OS_ARCH directory into the toolchain so that you will link with natively-compiled versions of the standard library. It walks all of the copied standard library and sets their modtimes so that they won't get rebuilt. It also copies some necessary auto-generated runtime source files for each platform (z*_) into the source directory to make it all work.
Example with gox:
Here's an example of how to cross-compile a project:
$ go get github.com/mitchellh/gox $ go get github.com/inconshreveable/gonative $ cd /your/project $ gonative build $ PATH=$PWD/go/bin/:$PATH gox
This isn't the most optimal way of doing things though. You only ever need one gonative-built Go toolchain. And with the proper GOPATH set up, you don't need to be in your project's working directory. I use it mostly like this:
One time only setup:
$ go get github.com/mitchellh/gox $ go get github.com/inconshreveable/gonative $ mkdir -p /usr/local/gonative $ cd /usr/local/gonative $ gonative build
Building a project:
$ PATH=/usr/local/gonative/go/bin/:$PATH gox github.com/your-name/application-name
- gonative is untested on Windows
- no linux/arm support because there are no official builds of linux/arm
- linux_386 binaries that use native libs depend on 32-bit libc/libpthread/elf loader. some 64-bit linux distributions might not have those installed by default