The GNU Compiler Collection installations are generally maintained by Johan Raber (firstname.lastname@example.org).
To use the GNU compilers you need to load the corresponding module, e.g.
module load gcc/4.7.2
The only included compilers of the suite are “gcc”, “g++” and “gfortran”. Using e.g. “gcc” can be done with
gcc -o example example.c
The GNU compilers are fully integrated with the NSC compiler wrappers with the exception of the module “gcc/4-centos6” which is the native, non-NSC-wrapped CentOS version. To use the native CentOS compiler with the NSC compiler wrapper, load the “gcc/system” module.