One of Scientific Linux's stronger points is its stability. It achieves this however by lagging considerably in its suite of default packages, even those provided by the EPEL repository. This is all well and good until some enthusiastic coven of programmers decide that their creation cannot exist without calling upon the most bleeding edge collection of dependencies. With this in mind we've provided a more modern version of the gcc compiler (4.6.1) in order to obviate the need for that awkward #include <iron-age.h> library call. However it still requires some paper-clips and string to hold it all together so you'll need the following in your .bashrc file: LD_LIBRARY_PATH=/opt/exp_soft/mpc-0.9/lib:/opt/exp_soft/mpfr-3.0.1/lib:/opt/exp_soft/gmp-5.0.2/lib:/opt/exp_soft/gcc-4.6.1/lib/:/opt/exp_soft/gcc-4.6.1/lib64:$LD_LIBRARY_PATH COMPILE_OF=/opt/exp_soft/gcc-4.6.1/bin:/opt/exp_soft/gcc-4.6.1/lib:/opt/exp_soft/binutils-2.21.1/bin PATH=$COMPILE_OF:$PATH CPATH=/opt/exp_soft/gcc-4.6.1/include And yes, we're aware that 4.6.2 was released (or escaped) less than a month ago. At some stage we may explore other OS's to support our HPC infrastructure, however this all depends on how our investigation into cloud based provisioning pans out. As is usually the case there's a balance between swings and round-abouts, and providing HPC completely independent of OS and architecture is a noble but elusive pursuit.