Install the cross compiler

This article illustrated how to install on a Ubuntu Linux PC a complete toolchain to cross compile for ARM9 the full Linux Kernel, Linux device drivers, Linux application or your own C and C++ applications.

Originally written by Lee McLoughlin

Although the Netus is completely capable of compiling applications and the kernel natively on the Netus itself cross compiling can be considerably faster. My Core 2 Duo 2 1 Gigabyte RAM PC can cross compile programs at least 10 times faster and for big programs over 20 times faster.

A few years back the people behind the ARM cpu range improved the way function calls were made. This new technique was called the “Embedded Abstract Binary Interface” or EABI for short. The ARM design also allowed for both big-endian and little-endian byte arrangements. The Netus is setup to use the new EABI as little-endian - ARM EABI little - or ARMEL for short.

Emdebian is short for the Embedded Debian Project an ongoing project to build Debian for small ARM based systems. In the long term I'm sure projects will be able to use all the space saving advances of Emdebian's Grip and Crush highly compact set ups. But here we are just going to use its ARM cross compiler capable of being run on Intel processors.

As root edit /etc/apt/sources.list and add the following to the end of the file:

#
# -- Emdebian cross toolchains
#
# deb http://www.emdebian.org/debian/ unstable main
# deb http://www.emdebian.org/debian/ testing main
deb http://www.emdebian.org/debian/ lenny main

Now we need to tell apt to use this new repo':

sudo apt-get install emdebian-archive-keyring
sudo apt-get update

Finally we can install the GCC, G++ cross compilers and support programs

sudo apt-get install libc6-armel-cross libc6-dev-armel-cross
sudo apt-get install binutils-arm-linux-gnueabi
sudo apt-get install gcc-4.3-arm-linux-gnueabi
sudo apt-get install g++-4.3-arm-linux-gnueabi
sudo apt-get install uboot-mkimage
sudo apt-get install apt-cross dpkg-cross
sudo apt-get install libncurses5-dev

If you plan on cross compiling non-kernel code also add the following:

sudo apt-get install linux-libc-dev-armel-cross

(Thanks to Doug Gilbert for this one.)