Cross compilation

To support cross-compilation, voyager distinguishes between the build architecture and host architecture. The build architecture is that of the system voyager and the compiler run on. The host architecture is that of the system your build products will run on. This distinction is important when fetching build tools from voyager - they should always be packages for the build system.

For the configuration file, this means that the build_tools dependencies are downloaded for the build architecture, while libraries dependencies are downloaded for the host architecture.

The build architecture is defined by the default_arch field in the configuration file or the environment variables. When not explicitly defined, the host architecture defaults to the build architecture. The host architecture can be defined while running voyager install:

$ voyager install --host ARM.GCC.481
$ voyager install --host-file Platforms/Windows-Platform.json

Windows-Platform.json:

{
  "version": "1",
  "host": ["MSVC.142.DBG.32", "MSVC.141.DBG.32", "MSVC.140.DBG.32", "go.windows.amd64", "windows"]
}