One of the available GNU Fortran compilers is the
g95 compiler
with the
g95 home page.
It is called with g95.
Important switches are:
-fendian=big: With this flag set, binary files in
big_endian format
(the standard for UIO files)
are automatically transformed to
little_endian
and vice versa.
-O3: General optimization flag.
In 3.6 the preprocessor switches are listed, that control the
modern - single - version uio_mac_module.F90.
OpenMP is not there yet. The binary I/O format (``unformatted'') is incompatible with the one used before in CO5BOLD: no existing UIO files can be read.