Cross-compilation for Raspberry Pi in GCC. Where to start?
TL/DR: Where can I find more information about building a GCC 4.7.0 cross-compiling toolchain for ARM (gnueabi) platform (intended to run on a Raspberry Pi device)?
I have just got a brand new Raspberry Pi and I am very eager to start programming for it. I've managed to install the GCC toolchain (I am using the Arch Linux system image) and compiled some basic programs, all working fine.
I've also tried to compile the Boost libraries because I often use them in my projects and everything seemed to work fine by following the instructions (./bootstrap.sh + ./b2) except for the fact that the compilation was painfully slow. I left it on for a few hours but it barely got past the first few source files. After I left it running for the night, I discovered that the build process aborted due to RAM shortage.
So, my guess is that Rasp Pi is simply underpowered for compiling something of such size as Boost. So, cross-compilation comes to my mind. However, even though there is a lot of information about ARM cross compilation available online, I find it confusing. Where does one even start?
I have a recent GCC version (4.7.0) available on my Raspberry Pi, so I would ideally like to cross-compile with the same version. Where can I get the GCC 4.7.0 toolchain for ARM? (I will be compiling on x86 CentOS 6.2)
Edit:
I deallocated unneeded GPU memory and set up a 4GB swap partition on a USB drive, while build files are on a NFS share. Boost is now compiling much much faster, so it is manageable. I would still like to know how can I set up a GCC 4.7 toolchain for cross compilation on my x86 PC though, since I intend to do a lot of compiling and I would like it to be as fast as possible.
Edit 2:
Since GCC 4.7.0 is relatively new, there does not seem to be a pre-built cross-compiler (i386->ARM). I will probably have to build one myself, which seems an non-trivial task (I've tried and failed). Does anyone know of a tutorial to follow for building a GCC cross-compiler, hopefully for one of the recent versions?
I've tried with this great shell script (which worked great for building a same-arch compiler) and I've successfully built binutils and GCC's prerequisites, but then GCC build kept failing with many cryptic errors. I am really lost here, so I would greatly appreciate your help.
GCC on Raspberry Pi was configured with
--prefix=/usr --libdir=/usr/lib --libexecdir=/usr/lib
--mandir=/usr/share/man --infodir=/usr/share/info
--with-bugurl=https://bugs.archlinux.org/
--enable-languages=c,c++,fortran,lto,objc,obj-c++ --enable-shared
--enable-threads=posix --with-system-zlib --enable-__cxa_atexit
--disable-libunwind-exceptions --enable-clocale=gnu
--disable-libstdcxx-pch --enable-libstdcxx-time
--enable-gnu-unique-object --enable-linker-build-id --with-ppl
--enable-cloog-backend=isl --enable-lto --enable-gold
--enable-ld=default --enable-plugin --with-plugin-ld=ld.gold
--with-linker-hash-style=gnu --disable-multilib --disable-libssp
--disable-build-with-cxx --disable-build-poststage1-with-cxx
--enable-checking=release --host=arm-unknown-linux-gnueabi
--build=arm-unknown-linux-gnueabi
Edit 3:
I managed to build a 4.7 GCC toolchain for ARM (yay!) using this shell script as suggested by user dwelch in the comments. I also built newlib and libstdc++ using this article as a guide. The toolchain works fine, but hen I run the executable on my Raspberry Pi, it fails with Illegal instruction. What could be the cause of that?
Answer
I found these instructions How to build a cross compiler for your Raspberry Pi. It is a great walk through using a crosstool-ng tool which simplifies configuring a cross-compiler build A LOT (it has a nice curses-based interface) and it supports GCC 4.7.
Seems to work great!