C++ is a bit tricky. It will have a runtime load impact if the MPI provider exports the C++ interface from a DLL (because of the C++ func signature change). If the C++ interface was provided as a static library (or as an inline implementation in the header) that links to the C bindings, there is no runtime impact and the application does not need to rebuild. Thanks, .Erez -----Original Message----- From: mpi-22-bounces_at_[hidden] [mailto:mpi-22-bounces_at_[hidden]] On Behalf Of Jeff Squyres Sent: Saturday, April 04, 2009 9:21 AM To: MPI 2.2 Subject: [Mpi-22] MPI-2.2 -- change ABI or not? On Apr 4, 2009, at 9:53 AM, Jeff Squyres (jsquyres) wrote:

But the general point may need broad discussion next week -- have we been sure to adhere to the "must be ABI compatible" rule for all MPI-2.2 issues?

(changed the subjet to be more accurate) I notice that ticket #5 has already had a 1st reading; it will certainly change the ABI. My point: if we are taking a hard line to make it possible for any existing MPI-2.1 application to be able to run against MPI-2.1 and MPI-2.2 versions of the same implementation, we will need to review all MPI-2.2 tickets. -- Jeff Squyres Cisco Systems _______________________________________________ mpi-22 mailing list mpi-22_at_[hidden] http://lists.mpi-forum.org/mailman/listinfo.cgi/mpi-22