XL Fortran Enterprise Edition for AIX : User's Guide - IBM

Editing, Compiling, Linking, and Running XL Fortran
Programs
Most Fortran program development consists of a repeating cycle of editing,
compiling and linking (which is by default a single step), and running. If you
encounter problems at some part of this cycle, you may need to refer to the
sections that follow this one for help with optimizing, debugging, and so on.
Prerequisite Information:
1. Before you can use the compiler, all the required AIX settings (for example,
certain environment variables and storage limits) must be correct for your user
ID; for details, see “Correct Settings for Environment Variables” on page 12.
2. Before using the compiler for a specialized purpose, such as porting or
performance tuning, look at the categories of options in “Summary of the XL
Fortran Compiler Options” on page 67 to see if XL Fortran already provides a
solution.
3. To learn more about writing Fortran programs, refer to the XL Fortran Enterprise
Edition for AIX Language Reference.
Note that you can substitute references to libxlf90_r.a in this section with
references to libxlf90.a. This is because a link is provided from the libxlf90.a
library to the libxlf90_r.a library. You do not need to manually link with separate
libraries depending on whether you are creating a threaded or a non-threaded
application. XL Fortran determines at run time whether your application is
threaded.
Editing XL Fortran Source Files
To create Fortran source programs, you can use any of the available text editors,
such as vi or emacs. Source programs must have a suffix of .f unless the fsuffix
attribute in the configuration file specifies a different suffix or the -qsuffix
compiler option is used. You can also use a suffix of .F if the program contains C
preprocessor (cpp) directives that must be processed before compilation begins.
For the Fortran source program to be a valid program, it must conform to the
language definition that is specified in the XL Fortran Enterprise Edition for AIX
Language Reference.
Compiling XL Fortran Programs
To compile a source program, use one of the xlf90, xlf90_r, xlf90_r7, xlf95, xlf95_r,
xlf95_r7, xlf, xlf_r, xlf_r7, f77, fort77, f90, or f95 commands, which have the form:
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