[mvapich-discuss] mvapich1-0.9.9-beta suggestion for F90

[Shaun Rowland]

Bas van der Vlies wrote:
> Hello,
> 
>  I could not build the fortran90 mpich modules because we got an error:
> {{{
> checking whether Fortran 90 is compatible with Fortran 77... no
> configure: error: Fortran 90 and Fortran 77 compilers are not compatible.
> They generate external symbol names that are different.
> }}}
> 
> the following F90 flag solves the problem:
>   F90=gfortran  F90FLAGS="-ff2c" ./make.mvapich.gen2
> 
> Just a tip ;-)

Hi. I've looked into this some more. I think the F90FLAGS you mention
might only be necessary depending on the version of g77 and gfortran you
are trying to use. On our systems, I can use g77 and gfortran (for F77
and F90) without setting F90FLAGS. I assume you are trying to do this
and getting the error because the program should be from different
versions of GCC. So, if the above works and lets you use g77 and
gfortran, that's useful information.

What I suggested previously was using gfortran for both F77 and F90 as
later version of GCC just have that. This also will mean the Fortran
compilers are the same, so they should be "compatible". In order to do
this, you need to set the following environment variables:

F77=gfortran
F90=gfortran
F77_GETARGDECL=" "

We will put something in the User Guide about this.
-- 
Shaun Rowland	rowland at cse.ohio-state.edu
http://www.cse.ohio-state.edu/~rowland/