README.xlf

Building Abinit 6 with the IBM XL Fortran compiler
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Troubleshooting
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If the compiler complains about invalid syntax related to "config.h",
the most likely origin of the problem is an incorrect default setting of the
preprocessor options in the config file of xlf, explicitely asking to
leave C comments in the preprocessed file.

This is solved by editing "xlf.cfg", replacing:

  cppoptions = -C

by:

  cppoptions = -P

If you do not have write permissions on this file, then copy it into
your home directory before modifying it. It is usually located in "/etc"
or "/etc/opt/ibmcmp/xlf/<version>".

You will also need either to reconfigure Abinit the following way:

  ../configure FC="xlf -F /path/to/xlf.cfg"

or to force "make" to use the modified compiler:

  make FC="xlf -F /path/to/xlf.cfg"

Of course, do not hesitate to replace "xlf" by any other name if needed,
e.g. "mpif90".

If "make" succeed, you should probably consider asking your system
administrator to edit the system-wide config file or create another
one.