On the SCC, there are currently three families of compilers: GNU, Portland Group Inc. (PGI), and Intel. They are used for compiling C, C++, and Fortran codes. The system default is 64-bit compilation, while 32-bit compilation is also available.
The GNU and PGI compilers are automatically available after logging onto the SCC. To switch to the Intel compiler, use the module command:
scc1% module load intel/2016 <-- load the Intel compiler
The commands for the three compilers are listed in the following table:
| Language | Developer | Command | MPI1 | OpenMP |
|---|---|---|---|---|
| Fortran 77 | GNU | gfortran | mpif77 | gfortran -fopenmp |
| Fortran 90/95/03 | GNU | gfortran | mpif90 | gfortran -fopenmp |
| C | GNU | gcc (cc)2 | mpicc | gcc -fopenmp |
| C++ | GNU | g++ (c++)2 | mpicxx (mpic++, mpiCC)4 | g++ -fopenmp |
| Fortran 77 | PGI | pgfortran (pgf77)3 | mpif77 | pgfortran -mp |
| Fortran 90/95/03 | PGI | pgfortran (pgf90, pgf95)3 | mpif90 | pgfortran -mp |
| C | PGI | pgcc | mpicc | pgcc -mp |
| C++ | PGI | pgc++ | mpicxx (mpic++, mpiCC)4 | pgc++ -mp |
| Fortran 77/90/95/03 | Intel | ifort | mpifort (mpif90, mpif77)5 | ifort -openmp |
| C | Intel | icc | mpicc | icc -openmp |
| C++ | Intel | icpc | mpicxx (mpic++, mpiCC)4 | icpc -openmp |
1 To facilitate ease of use, the individual wrapper (mpif77, mpif90, mpicc, and mpicxx) combines the respective compiler with its corresponding header file and MPI library.
Note: The MPI commands point to the GNU compiler by default (e.g., mpicc points to the gcc). See Compile An MPI Program for how to switch to the PGI or Intel compilers.
2 cc is an alias for gcc; c++ is an alias for g++.
3 pgfortran works for Fortran 77/90/95/03 codes.
4 mpicxx, mpic++, and mpiCC work the same, no matter which compiler is in use.
5 mpifort, mpif90, and mpif77 work the same when the Intel compiler is in use.
GNU compilers
Here are some examples of commonly used flags applicable to gcc, g++, and gfortran compilers:
scc1% man gcc <-- gfortran manual (help) page
scc1% gcc --help <-- concise options help file
scc1% gcc -o file-name ... <-- executable name
scc1% gcc -On ... <-- code optimization; n=0,1,2,3; recommends 3
scc1% gcc -g ... <-- debug mode
scc1% gcc -Warray-bounds ... <-- arrays bound checking
scc1% gcc -pg ... <-- profiling
scc1% gcc -m32 ... <-- 32-bit compilation
See Multiprocessor Programming for how to compile OpenMP and MPI codes.
PGI compilers
Here are some examples of commonly used flags applicable to pgcc, pgc++, pgfortran compilers:
scc1% man pgcc <-- pgfortran manual (help) page
scc1% pgcc -help <-- concise options help file
scc1% pgcc -o file-name ... <-- executable name
scc1% pgcc -On ... <-- code optimization; n=0,1,2,3,4,fast; recommends 3
scc1% pgcc -g ... <-- debug mode
scc1% pgcc -pg ... <-- profiling
scc1% pgcc -m32 ... <-- 32-bit compilation
Go to the Multiprocessor Programming page on how to compile OpenMP and MPI codes.
Intel compilers
Here are some examples of commonly used flags applicable to icc, icpc, ifort compilers:
scc1% man icc <-- icc manual page
scc1% icc -help <-- concise options help file
scc1% icc -o file-name ... <-- executable name
scc1% icc -On ... <-- code optimization; n=0,1,2,3,4,fast; recommends 3
scc1% icc -fast ... <-- accelerate the program (recommended)
scc1% icc -g ... <-- debug mode
scc1% icc -p ... <-- profiling (-pg is also valid)
scc1% icc -m32 ... <-- 32-bit compilation
Go to the Multiprocessor Programming page on how to compile OpenMP and MPI codes.