Raspberry cross-compiling

I want to cross-compile some stuff for my Raspberry, this is a (memo for me) tutorial to do that.

1. Take crosstool-ng from here,  here or here (the last two are mirror, use them only if the official website is not working)
2. you need some dependencies:
   apt-get install gcc gperf bison flex gawk libtool automake libncurses5-dev
3. go into the crosstool-ng directory and:
   ./configure--prefix=path_where_to_put_the_files/
   make
   makeinstall
   cpct-ng.comp /etc/bash_completion.d/
4. after I setup some bash vars in my .bashrc:
   export WORKSPACE=~/workspace
export RASPBERRY=$WORKSPACE/raspberry
export CROSS_INST_PATH=$RASPBERRY/crosstool-ng/installer/
export PATH="$PATH:$CROSS_INST_PATH/bin"
5. and after to use them:
   source ~/.bashrc
6. go into path_where_to_put_the_files and:
   ct-ng menuconfig
7. the important options are:
   • Paths and misc options
     • (Important) Enable “Try features marked as EXPERIMENTAL“
     • (Optional) Change “Prefix directory” (for example, you can put “$RASPBERRY/crosstool-ng/x-tools/${CT_TARGET}” there)
   • Target options
     • (Important) Change “Target architecture” to “arm“
     • (Important) Leave “Endianness” set to “Little endian“
     • (Important) Leave “Bitness” set to “32-bit“
   • Toolchain options
     • (Nothing to do here, the defaults are fine)
   • Operating system
     • (Important) Change “Target OS” to “linux“
   • Binary utilities
     • (Optional) Change “binutils version” to “2.21.1a” or whichever is the latest that isn’t marked as experimental
   • C compiler
     • (Optional)”Show Linaro versions (EXPERIMENTAL)“. In the “gcc version” field, choose the “linaro-4.6-2012.04 (EXPERIMENTAL) compiler“. You’re free to choose a different one but this one works well. We do recommend the Linaro versions over the vanilla ones for the RPi
     • (Optional) Enable “C++” under the group “*** Additional supported languages: ***” if you need g++ tool also built for your RPi toolchain
8. build the tool:
   ct-ng build
9. after I setup some others bash vars (these is the final file):
export WORKSPACE=~/workspace
export RASPBERRY=$WORKSPACE/raspberry
export CROSS_CC_PATH=$RASPBERRY/crosstool-ng/x-tools/arm-unknown-linux-gnueabi/
export CROSS_INST_PATH=$RASPBERRY/crosstool-ng/installer/
export PATH="$PATH:$CROSS_CC_PATH/bin:$CROSS_INST_PATH/bin"
10. after you are ready to compile, an example:
./autogen.sh --with-parameter-expansion-string-replace-capable-shell=/bin/bash --host=arm-unknown-linux-gnueabi --enable-static --prefix=$RASPBERRY/compile

Bibliography:

https://trac.ffmpeg.org/wiki/CompilationGuide/RaspberryPi

http://tech4research.wordpress.com/2014/03/04/installing-crosstool-ng-on-debian-7-4/