Kruco

This is a makefile that simplifies the creation of GCC cross-toolchains for a wide variety of target platforms.

The toolchains produced by this makefile are probably not appropriate for building production software. The point of this makefile is just to be able to type a single command and have a toolchain that is useful for development and testing purposes in less than 15 minutes.

Caveats

• This makefile is only tested regularly on modern Linux machines. It might work in other Unix-like environments, but we make no promises.
• The versions for Linux kernel headers, glibc, and musl are generally pinned to whatever the latest release of Zig supports.
• You need to install various build prerequisites yourself, including some libraries. The build is done in this way to reduce the size of the generated toolchains.

Usage

In a nutshell, usage is as follows:

1. Clone this repository.
2. Run make list to get a list of supported targets.
3. Run make <target> PREFIX=... to build and install a toolchain.
4. Run make clean to remove leftover build artifacts.

For example, make arm-linux-gnueabi PREFIX=$HOME/cross will install a toolchain targeting Linux and glibc under $HOME/cross/arm-linux-gnueabi with a sysroot under $HOME/cross/arm-linux-gnueabi/sysroot.

If you need to use your computer as an expensive space heater and/or you have a burning hatred for your CPU and disk drive, you can run make all to build a toolchain for every single supported target. That is 400+ toolchains, just to be clear. You probably should not do that. But you can.

Configuration

The following variables affect the makefile:

• PREFIX: The location to install the built toolchain in. Note that the toolchain will actually be installed under $PREFIX/<target>. Defaults to the out directory in the root of the repository.
• BUILD: The platform that you are building the toolchain on. This defaults to x86_64-cross-linux-gnu. The cross vendor component is crucial here, as it forces Autotools to run in cross-compilation mode. You only need to set this if you are building on a different platform, e.g. aarch64-cross-linux-gnu.
• JOBS: The maximum number of concurrent jobs that will be used while building each software package. Defaults to the output of nproc, i.e. as many jobs as you have CPU cores.
• V: Can be set to any value to get verbose output from the makefile.

License

The build system is licensed under the terms found in LICENSE-0BSD. Each software package that is built has its own license terms.