Installing Raspberry Pi Cross-Compiler

Question

I am attempting to get cross-compiling for Raspberry Pi working on my Ubuntu machine.

During my initial attempts I was using the arm-linux-gnueabi compiler, which is available in the Ubuntu repo. I got this working. I was able to build all my dependencies and use the cross-compiler in my cmake project.

However, I believe I should be using the hf version, so I switched to arm-linux-gnueabihf. Then I realized that this does not work with Raspberry Pi since it is armv6.

After some Googling, I then found the pre-built toolchain from GitHub: https://github.com/raspberrypi/tools.

I downloaded the toolchain, but I don't really understand how to "install" it. I extracted the files to my home directory. The directory structure looks like this:

/gcc-linearo-arm-linux-gnueabihf-raspbian
    /arm-linux-gnueabihf
        /bin
            (contains g++, gcc, etc)
        /lib
            (contains libstdc++ library)
    /bin
        (contains arm-linux-gnueabihf-g++, arm-linux-gnueabihf-...)
    /lib
        (gcc lib stuff)

If I change directory to the INNER bin folder I am able to compile a test program from the terminal without any problems.

~/tools/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian/
arm-linux-gnueabihf/bin$ g++ test.cpp -o test

I then tried to compile a test program in the OUTER bin folder, which contains the prefixed versions of the tools.

 ~/tools/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian/bin$ 
 arm-linux-gnueabihf-g++ test.cpp -o test

However, when I try to use the compiler now (from outside the inner bin directory), it is unable to find the libstdc++ shared library that comes with the toolchain:

arm-linux-gnueabihf-gcc: error while loading shared libraries: 
libstdc++.so.6: cannot open shared object file: No such file or directory.

Furthermore, I want to be able to use the compiler without having to navigate to the bin directory. So I tried adding the OUTER bin directory (since I want the prefixed versions) and both lib directories to my PATH:

export PATH=$PATH:~/tools/.../bin
export PATH=$PATH:~/tools/.../lib
export PATH=$PATH:~/tools/.../.../lib

However, this results in the same error. How should I "install" the toolchain so that I can use the toolchain from everywhere, just like I can when I use the cross-compilers from the Ubuntu repo?

Answer 1

The primary target of the Ubuntu arm-linux-gnueabi cross compiler is to compile for a different architecture of the same Ubuntu release leveraging the Debian/Ubuntu multiarch capabilities. Example: You compile on Ubuntu 16.04 amd64 for Ubuntu 16.04 armel.

If you would like to do a similar thing for Raspbian I suggest the following approach:

• On your Ubuntu host install Debian Jessie amd64 within a chroot or a LXC container.
• Enable the foreign architecture armhf.
• Install the cross compiler from the emdebian tools repository.
• Tweak the cross compiler (it would generate code for ARMv7-A by default) by writing a custom gcc specs file.
• Install armhf libraries (libstdc++ etc.) from the Raspbian repository.
• Build your source code.

Since this is a lot of work I have automated the above setup. You can read about it here: http://www.get-edi.io/Cross-Compiling-for-Raspbian/

Answer 2

I cannot reproduce the problem anymore

As of https://github.com/raspberrypi/tools/tree/5caa7046982f0539cf5380f94da04b31129ed521 it just works no matter which directory I'm on, just adding to PATH is enough:

git clone https://github.com/raspberrypi/tools
export PATH="$(pwd)/tools/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian-x64/bin:${PATH}"
printf '#include <stdio.h>\nint main() { puts("hello world"); }\n' > hello_world.c
printf '#include <iostream>\nint main() { std::cout << "hello world" << std::endl; }\n' > hello_world.cpp
arm-linux-gnueabihf-gcc -std=c99 -o hello_world_c hello_world.c
arm-linux-gnueabihf-g++ -std=c++11 -o hello_world_cpp hello_world.cpp

Tested in Ubuntu 17.10.

The official documentation also documents that this should work: https://www.raspberrypi.org/documentation/linux/kernel/building.md (GitHub)

Related: https://stackoverflow.com/questions/19162072/how-to-install-the-raspberry-pi-cross-compiler-on-my-linux-host-machine

Answer 3

You can try my Latest Pre-Built Open-Sourced GCC Toolchains for Raspberry Pi in this Sourceforge Project:

Latest Set of Pre-Built GCC Cross & Native Compiler Binaries for Raspberry Pi - v2.5

Project Summary: This project contains the UpToDate set of Precompiled/Pre-Built Raspberry pi GCC Cross & Native Compilers Binaries, saving your tons of time(No compiling or Error Handling needed whatsoever). Just Extract, Link & Enjoy complete GCC(Raspberry Pi) functionality in your Machine. You can use its native compilers for Raspberry Pi(Can be used along with old & slow 6.3.0 GCC), Or use the Cross-Compiler in any Linux Machine(Tested on Latest Ubuntu/bionic x64) to compile programs for your Raspberry Pi. All these compilers binaries are Raspberry Pi hardware optimized for enhanced overall performance.

Supported GCC Versions:

• GCC 6.3.0
• GCC 7.4.0
• GCC 8.2.0
• GCC 8.3.0

Supported Raspberry Pis:

• All Raspberry Pi versions/models are currently supported.
• Any other ARM Devices with similar Hardware configurations may also work.

Supported Environments:

• Cross-Compiler: All Linux Distros (x32/x64) are currently supported.
• Native-Compiler: All Raspberry Pi version/model with Raspbian OS is supported. Other OS may/may-not work.

Supported Languages:

• C++
• C
• Fortran

Answer 4

I created a project on Github which contains build files to build your own toolchain with correction versions. Especially the --with-arch=armv6 flag is important.

The corresponding project can be found here: https://github.com/Pro/raspi-toolchain