= Frequently Asked Questions =

== Compilation ==

=== Compilation with gfortran fails because of unrecognized command line option `-fallow-argument-mismatch` ===

If this happens, please delete this option in the compile include file in `make.arch`. This option is necessary for compilation with gfortran 10, but older versions of gfortran don't seem to even know this option. 

=== Compilation with gfortran fails with an error about a `Type mismatch` related to MPI_allreduce or some other MPI function ===

If this happens, please specifcy `-fallow-argument-mismatch` in the compile include file in `make.arch` in the line 'OPT = ....'.
gfortran from version 10 checks the arguments more strictly than older version of gfotran. The apparent argument mismatch is actually allowed in the call to functions of MPI.