Emdebian Cross Development Environment

Emdebian Cross Development Environment

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Emdebian toolchain building Howto

Below is documented the build process for building cross-toolchains the 'Debian Way'. You only need to do this if the pre-built binary toolchains do not satisfy your needs for some reason.

A more up to date document can be found at Debian wiki.

We use the buildcross script to build the toolchains, it is also provided as a Debian package in the experimental suite. (buildcross replaces the old compbuildscript and emchain.)

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Notation and exactly what things are called is important otherwise there can be much confusion, so we will clarify:

When building toolchains:

build == host

Build     machine installing the cross compiler       build
Host      machine running the cross compiler          host
Target    machine for which the compiler builds code  target

When building packages:

build != host

build     machine running the cross compiler           build
host      machine running the built package            handheld device
there is no particular meaning for 'target'.

Building your own toolchain is not a trivial matter, although this method is actually quite strightforward.

• gcc-4.0 or later

  First get all the necessary build dependencies:

  $ apt-get install dpkg-cross apt-cross fakeroot dpatch gawk flex realpath automake1.7 debhelper cdbs

  This is not a complete list, of course you need gcc, but these are the most often forgotten ones.

  Get the necessary sources :

  $ apt-get source gcc-4.4 binutils

  $ cd binutils-2.x
  $ TARGET=$linux-architecture fakeroot debian/rules binary-cross (replace arch by arm, alpha,...)

  Note that binutils versions above 2.20.51, have changed syntax to support TARGET=$linux-architecture dpkg-buildpackage -b -uc -us

  Once the build is finished you have to install the package that was created with dpkg -i

  For the next step you can use the existing Debian packages for your target architecture, after converting them with dpkg-cross, for the kernel-headers, and the related architectures

  Download, convert and install the packages for libc6, libc6-dev and linux-libc-dev for your target architecture.

  $ dpkg-cross -a $architecture -b $package

  You can also try a other tools trying to do smarter things as xapt package which replaces apt-cross and it is not available from squeeze, so get it from squeeze backports or wheezy.

  $ xapt -a arch package

  When this process was succesful, we start with the last steps. We have to build the actual compiler.

  $ export GCC_TARGET=arch (replace arch through arm, alpha,...)
  $ cd gcc-4.4-x
  $ fakeroot debian/rules control
  $ dpkg-buildpackage -b -rfakeroot
  

  After a succesful build, install the newly created gcc packages with dpkg -i package-name. These are (for arm):

  • libstdc++6-armel-cross_4.4.x_all.deb
  • libstdc++6-dev-armel-cross_4.4.x_all.deb
  • g++-4.4-arm-linux-gnueabi_4.4.x_i386.deb
  • gcc-4.4-arm-linux-gnueabi_4.4.x_i386.deb
  • cpp-4.4-arm-linux-gnueabi_4.4.x_i386.deb
  • libgcc1-arm-cross_4.4.x_all.deb
  • gcc-4.4-arm-linux-gnueabi-base_4.4.x_i386.deb

  
  Now you should have a brand new cross-compiler at your disposal.

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