docker-arm-cross-toolchain

Repository with ARM cross-compilation toolchains, built using Docker and crosstool-NG.

Includes C, C++ and Fortran cross-compilers (GCC 11.2), including the address and undefined behavior sanitizers (Asan and UBsan), cross-GDB and gdbserver (10.2). Compatible with glibc 2.28 and Linux 5.8 or later. These cross-compilers have been patched for Debian Multiarch.

Download

Docker images are available from GitHub Packages, and the ready-to-use toolchains can be downloaded from the Releases page.

Direct links:

• aarch64-rpi3-linux-gnu (64-bit, RPi 2B rev. 1.2, RPi 3B/3B+, CM 3, RPi 4B/400, CM 4, RPi Zero 2 W)
• armv8-rpi3-linux-gnueabihf (32-bit, RPi 2B rev. 1.2, RPi 3B/3B+, CM 3, RPi 4B/400, CM 4, RPi Zero 2 W)
• armv6-rpi-linux-gnueabihf (32-bit, RPi A/B/A+/B+, CM 1, RPi Zero/Zero W)

For modern Raspberry Pi boards running 64-bit Raspberry Pi OS or 64-bit Ubuntu, use the aarch64-rpi3-linux-gnu toolchain.

For modern Raspberry Pi boards running 32-bit Raspberry Pi OS, use the armv8-rpi3-linux-gnueabihf toolchain.

For older Raspberry Pi boards, or if you need to support all boards, use the armv6-rpi-linux-gnueabihf toolchain.

There is no specific toolchain for the first version of the RPi 2B (which uses a quad-core ARMv7 Cortex-A7), but the armv6-rpi-linux-gnueabihf toolchain is compatible with this architecture as well.

For the RPi 4B/400 and the CM 4, use the aarch64-rpi3-linux-gnu or the armv8-rpi3-linux-gnueabihf toolchain, depending on whether you're using a 64-bit or a 32-bit operating system. For optimal performance, you can include the -mcpu=cortex-a72 or -mtune=cortex-a72 flags (GCC ARM options).

Installation

Download the archive of the toolchain you need using the links above. Then extract it to a convenient location, e.g. ~/opt.

You can download and extract the toolchain in one go using wget and tar, for example:

mkdir -p ~/opt
wget -qO- https://github.com/tttapa/docker-arm-cross-toolchain/releases/latest/download/x-tools-aarch64-rpi3-linux-gnu.tar.bz2 | tar xJ -C ~/opt

If you want to use the toolchain directly, you can add the ~/opt/x-tools/aarch64-rpi3-linux-gnu/bin folder to your path:

export PATH="$HOME/opt/x-tools/aarch64-rpi3-linux-gnu/bin:$PATH"

To make it permanent, you can add it to your ~/.profile:

echo 'export PATH="$HOME/opt/x-tools/aarch64-rpi3-linux-gnu/bin:$PATH"' >> ~/.profile

Usage

For new software configured using CMake, use a CMake toolchain file. Examples can be found in https://github.com/tttapa/RPi-Cross-Cpp-Development/tree/master/cmake.

I highly recommend using CMake for your own projects as well, this makes it much easier for other people to depend on, package, and cross-compile your software.

For legacy software configured using Autotools, you usuall have to set a flag --host="aarch64-rpi3-linux-gnu" when invoking the configure script.
Packages with custom configuration scripts might have differently named options, for example, OpenSSL has --cross-compile-prefix="aarch64-rpi3-linux-gnu-".
Custom Makefiles might require you to set a variable such as CROSS=aarch64-rpi3-linux-gnu- or CROSS_COMPILE=aarch64-rpi3-linux-gnu-.
If all else fails, try setting the CC, CXX or FC environment variables explicitly.

For more detailed instructions on how to cross-compile software and how to handle dependencies, see https://tttapa.github.io/Pages/Raspberry-Pi/index.html.