View source for Compile for the PhatBox

[[Category:HOWTO]]
Here are some notes on how to compile C programs to run on the PhatBox.  It's from memory, so some of the details may be slightly wrong -- please edit this page if you have any corrections.  --bushing

= Cross-Compiler =
Build a cross-compiler for ARM (the processor used in the PhatBox). The PhatBox guys used gcc-2.95.3, so that's what I used.

The [http://kegel.com/crosstool/ crosstool] utility makes this very easy under Unix-like systems (e.g. Linux).

The configuration files I used were:

''arm.dat''
 KERNELCONFIG=`pwd`/arm.config
 GCC_EXTRA_CONFIG="--with-cpu=arm7tdmi --enable-cxx-flags=-mcpu=arm7tdmi"
 TARGET=arm-linux
 TARGET_CFLAGS="-Os"
 GLIBC_EXTRA_CONFIG=--enable-omitfp

''demo-arm.sh''
 #!/bin/sh
 set -ex
 TARBALLS_DIR=$HOME/downloads
 RESULT_TOP=/opt/crosstool
 export TARBALLS_DIR RESULT_TOP
 GCC_LANGUAGES="c,c++"
 export GCC_LANGUAGES
 eval `cat arm.dat gcc-2.95.3-glibc-2.1.3.dat` sh all.sh --notest

''(As root) create the directory /opt/crosstool and make it writable by you, and finally (as you) run the demo script, e.g.''
 $ sudo mkdir /opt/crosstool
 $ sudo chown $USER /opt/crosstool
 $ sh demo-arm.sh

...and wait for it to compile.

= libc =
In order to actually compile programs, you also need a libc (c library).  Crosstool will build you a glibc, but none of the programs I compiled with it actually worked. 

So, I turned to [http://www.fefe.de/dietlibc/ diet libc - a libc optimized for small size].   I found that I had to first make a version for i386 (to get the build-i386/diet program), and then I could build a version for arm.  IE:

 $ make
 $ make arm

You will then have a program called ''diet'' in the bin-i386 directory.  Copy this into your path, and then you can build programs for the PhatBox by running

 $ diet arm-linux -o hello hello.c

(this is a GCC wrapper)