[O-MPI users] [Beowulf] MPI ABI

[Greg Lindahl]

On Tue, Oct 11, 2005 at 03:44:07PM +0200, Toon Knapen wrote:

> The one thing about linking f77 and C that I do not know how to solve
> yet is e.g. fortran functions that return a complex.

On x86 and AMD64, this is the f2c-abi issue, and is not present in the
MPI API. If you experiment on AMD64 systems, you'll find that some
compilers do it the way documented in the g77 info files, some follow
the platform ABI (PathScale), and some do half and half (probably an
accident.) So it's really handy that MPI doesn't have any such calls.
Functions returning REAL*4 are the other piece of the f2c-abi issue.

-- greg