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Compilers on Research Computing Linux Systems


Most Research Computing Linux computers have three different kinds of compilers: GNU compilers, Portland Group compilers, and Intel compilers.

Below is a table that shows the different compilers and their commands.

  Fortran 77   .f   pgf77   Portland Group
    .f   ifort   Intel
    .f .F .for   gfortran   GNU
  Fortran 90   .f .f90   pgf90   Portland Group
    .f .f90   ifort   Intel
  C   .c   pgcc   Portland Group
    .c   icc   Intel
    .c   gcc   GNU
  C++   .c .C   pgCC   Portland Group
    .c   icc   Intel
    .c   g++   GNU
  • In general, gcc/g++ is the most flexible since it runs on a variety of different computer platforms. Many people use gcc/g++ so it will be easy to port their code to other platforms. gfortran is the Fortran GNU compilers.
  • The Portland Group compilers will compile f77, f90, C, and C++ codes. Many Fortran codes use extensions to the language, and the Portland Group compilers support those extensions. Portland Group recommends you use the pgf90 for both Fortran 90 and Fortran 77 codes to gain additional code speed up.
  • The Intel compilers do a good job of compiling code to make use of the architectural features of the Intel processors.

Here is a table of frequently used compiler flags, common to the above compilers.

  -c  Produce an object file only.
  -o filename  Create an executable called filename (default is a.out).  
  -O {0, 1, 2, 3}    Specify the optimization level ( 0 is none and 3 is most aggressive).   
  -g  Include a symbol table, needed for debugging.
  -pg  Generate profiling code.
  -l  Look for include files in this directory (default include directory is /usr/include).  
  -L  Look for libraries in this directory (default library directory:  /lib, /usr/lib/usr/lib64). 
  -larchive  Link in a library called (or .a).
  -static  Link only with static libraries (compilers use shared libraries by default).

For more options and detailed information, consult man pages (e.g., man gcc). Send questions, corrections, or additional information about these compilers to [email protected].

Research Computing
Research Computing Consulting
Last updated: 
Tuesday, January 2, 2018
linux programming

If you have questions or need further information, contact your department's IT support office, or contact the IT Service Desk via email at [email protected], via phone at 603-646-2999 or walk in to see them in Baker/Berry 178J.

Information, Technology & Consulting