On Thu, 8 Jul 2010 09:53:11 -0400, Jeff Squyres <jsquyres_at_[hidden]> wrote:
> > Do you "use mpi" or the F77 interface?
> It shouldn't matter; both the Fortran module and mpif.h interfaces are the same.
Yes, but only the F90 version can do type checking, the function
prototypes are not present in mpif.h. The truncation is an internal
issue, unrelated to user code having compatible types (since I can
reproduce the issue from C). I'm just confused by how passing an int64
when an int32 is expected could work from Fortran on a big-endian system
(it would likely work from C when the argument is passed by value in a
register), using the F90 module would enable the compiler to do type
checking and should hilight any type mismatches.