* Tobias Burnus wrote on Thu, Mar 03, 2011 at 12:04:12AM CET: > Ralf Wildenhues wrote: > >The library will depend on the MPI installation, obviously. > >You can make a new target directory and overwrite CC with MPICC > >for that directory. For choosing the latter, the AX_MPI macro from > >the Autoconf Macro Archive can help. (I can help with the configure > >setup if needed, just not timely). > > OK. Though as it should be a relatively small library with little > dependency, I assume many users/system administrators will compile > it separately.
That should be even easier then. > >> MPI_Init (argc, argv); > >If you're relying on MPI2 anyway, I suggest you try to not limit your > >users to not use MPI themselves. So please use MPI_Initialized, and > >don't finalize if the library isn't responsible. > > Well, the current implementation relies on an early initialization > by the front end, the compiler generates a main program, which > initializes the library. Thus, there is no chance for the user to > call MPI earlier. Ouch. That then also means that the user will not be able to use MPI herself in the program: for them, MPI_Init first thing in main is the documented way to initialize MPI, but it will invoke undefined behavior with above setup. > However, one should think of having a coarray > program, where the main program is not a Fortran program. In that > case, the parallelization library could be called later. However, > one then runs into issues like initializing the library. I think one > has to think carefully about that - but supporting coarrays with a > non-Fortran main program causes several subtle issues. Could be; but I think you should aim for something like that in the end, it would be significantly more user-friendly. Thanks, Ralf
