Installing GCC-4.3.1

I sometimes see even seasoned developers be reluctant to use a different gcc version (ie. to reproduce a potentially compiler-specific issue or just to experiment with new optimisations or features). The reason is a fear of breaking their system by installing multiple compilers, or even by replacing their system compiler with a new one.

But actually it is very easy to install multiple gcc versions without any risk of “polluting” the development environment. At least on Debian or Debian-based distributions (I am using Ubuntu) which can automatically install dependencies.

    sudo apt-get build-dep gcc-4.1 g++-4.1

That is a brilliant feature of Debian apt, a life-saver when compiling sources with complex dependencies.

Here is how it goes:

    cd /usr/local/src/
    wget ftp://ftp.fu-berlin.de/unix/languages/gcc/releases/gcc-4.3.1/gcc-core-4.3.1.tar.bz2
    wget ftp://ftp.fu-berlin.de/unix/languages/gcc/releases/gcc-4.3.1/gcc-g++-4.3.1.tar.bz2
    mkdir gcc-4.3.1
    cd gcc-4.3.1/
    bzip2 -dc ../gcc-core-4.3.1.tar.bz2 | tar xf -
    bzip2 -dc ../gcc-g++-4.3.1.tar.bz2 | tar xf -
    mkdir build
    cd build
    ../gcc-4.3.1/configure --prefix=/usr/local/src/gcc-4.3.1 --disable-multilib
    time make -j4
    make install

These days it doesn’t even take long to build, just under 15 minutes on a 2.4GHz Q6600 (cheap quad-core Intel).

Now, the new GCC is installed in a completely seperate location, so it does not interfere in any way with normal work. But to use it to build some particular software, just do something like this:

    PATH="/usr/local/src/gcc-4.3.1/bin:$PATH" ./configure
    PATH="/usr/local/src/gcc-4.3.1/bin:$PATH" make

Well, there is one snag, that is why I have the –disable-multilib in the above ./configure. Otherwise I get this:

    In file included from /usr/local/src/gcc-4.3.1/build/./gcc/include-fixed/features.h:355,
             from /usr/include/stdio.h:28,
             from ../../../../gcc-4.3.1/libgcc/../gcc/tsystem.h:90,
             from ../../../../gcc-4.3.1/libgcc/../gcc/libgcc2.c:33:
    /usr/include/gnu/stubs.h:7:27: error: gnu/stubs-32.h: No such file or directory

This is some problem with Ubuntu Feisty which puts that include file in /usr/include/i486-linux-gnu/gnu/stubs-32.h where apparently GCC does not look for it. I do not need to build any 32-bit binaries, so –disable-multilib is a quick solution.

Hopefully this is fixed somehow in Hardy.