Building Pixel on Windows

Normally, it is sufficient to grab the Go MSI installer from the website in order to set up the toolchain. However, some packages that provide Go wrappers for C libraries rely on cgo tool, which in turn, needs the GCC toolchain in order to build the glue code. Also, 3rd-party dependencies are usually hosted on services like GitHub, thus Git is also needed. This mini-guide illustrates how to setup a convenient development environment on Windows using MSYS2.

Go

Follow the official instructions on Go website and install it, if you haven't done this yet. The default installation directory is usually fine for most users. Afterwards, locate the go.exe executable in the bin folder of the installation root and annotate the path to it. Typical path usually looks like C:/Go/bin.

MSYS2

The MSYS2 project aims to provide an isolated POSIX-like environment and a versatile package manager for easy software configuration and building on Windows.

Please follow the guide on the website and after having completed the setup, open the MSYS2 MSYS shell from Windows menu, which will spawn a terminal with a Bash shell.

MSYS2 uses Pacman as package manager for automated software installation and we will use it to bootstrap our development environment.

GCC toolchain

The GCC compiler suite and the development libraries needed for cgo can be installed with just one command:

pacman -S --needed base-devel mingw-w64-i686-toolchain mingw-w64-x86_64-toolchain

Then add it to $PATH:

echo 'export PATH=/mingw64/bin:$PATH' >> ~/.bashrc

Git

There are two options available for Git installation: either from the website or via pacman. If you have Git already installed via official installer, locate the path to git.exe executable in the installation path and annotate it. Otherwise, install it via pacman:

pacman -S git

Environment setup

The PATH and GOPATH environment variables need to be propery configured to point to Go and Git executables. We'll append their initialization to user's local .bashrc file, which holds Bash shell customization.

NOTE: All paths should be specified in UNIX filesystem notation, although this is not a strict requirement, since Bash translates Windows paths to Unix automatically, but it helps keep consistency and prevents some nasty situations. In MSYS2 environment, drive letters (C:, D:, etc) start from root (/), for example: C:\Windows translates to /c/Windows. Backslash (\) is used for spaces escaping. Case does not matter, alhtough it's preferable to maintain it.

Go tools path

Recall the path to go.exe binary and append it to .bashrc, if the default Go installation path was used, the command will look like this:

echo 'export PATH=/c/Go/bin:$PATH' >> ~/.bashrc

Git path (optional)

This is needed only if Git was installed via official installer, as MSYS2 does not know where to locate the git.exe binary. For a standard Git installation the command will be:

echo 'export PATH=/c/Program\ Files/Git/bin:$PATH' >> ~/.bashrc

GOPATH (optional)

This variable specifies the root for Go package sources and binaries. Since Go 1.8 it is not mandatory anymore, and on Windows it defaults to %USERPROFILE%\Go, which is normally a path like C:\Users\username\Go. If you need it to point to a different location, append the override command to .bashrc, for example:

 echo 'export GOPATH=$USERPROFILE/go' >> ~/.bashrc

Building Go packages

From now on, all development will be done in the just configured MinGW shell. Note that this is not the MSYS2 shell we just used! The former is where development occurs, like building C/C++ or Go programs for Windows, the latter is used for the subsystem management, package installation, etc. Although both shells share the same .bashrc, the MinGW shell has additional configuration, and for example, picks the right toolchain based on the chosen architecture. From Windows menu, open the MinGW shell from the launcher provided by MSYS2, for the x64 architecture it is called MSYS2 MinGW 64-bit.

Now we can build and execute Go packages in an environment which closely resembles a typical UNIX one.

The following example checks out and builds the platformer demo of the Pixel 2D game development framework. Its hardware-accelerated backend uses go-gl package, which provides a Go wrapper for OpenGL C libraries.

go get github.com/faiface/pixel
cd $(go env GOPATH)/src/github.com/faiface/pixel/examples/platformer
go get
go build
./platformer.exe