The SGI Altix is running an SGI augmented version of RedHat Linux and has both Gnu and Intel (ver 7) compilers available.
The Intel compilers provide better performance and built in parallel/MPI capabilities.
The GNU compilers are accessed by simply "g77" for FORTRAN, or "gcc" for C. They should really only be used for debugging or code development.
The Intel compilers are "efc" and "ecc". You do need to have /opt/intel/compiler70/ia64/bin in your path - this is usually defined in your ".cshrc" file by default.
Compiler Flags
| Compiler Flag | Description |
|---|---|
| -w95 -cm | Suppress warnings and comments (makes it easier to see just error messages) |
| -tpp2 | Optimize for Itanium2 CPU |
| -O2 | Standard optimizations |
| -O3 | Aggressive optimizations, check both results and speed versus -O2 when using this |
| -ip | Interproceedural optimization |
| -ftz | Flush denormalized results to zero |
| -parallel | Auto parallelizing |
| -openmp -lmpi | For MPI/OpenMP programs, the -lmpi links to the MPI libraries |