On Jan 24, 2010, at 9:21 PM, Snir, Marc wrote:
I would suggest to use explicitly 64 bit integers as the type of count in the new functions. I.e., int64_t in C and INTEGER(KIND=8) in Fortran. Both types are part of the (C/Fortran) standard.
FWIW, I mentioned the above point on the MPI3 Fortran WG mailing list and got this reply:
Please do not touch any of the <stdint.h> stuff with a bargepole! Stick to the basic types and MPI type names.
There are many different ways where <stdint.h> integers cause portability, efficiency and other problems. Inter alia, the current revision of C is thinking of changing them in ways that could be incompatible with old code, and they are semantically incompatible with Fortran and many other languages in several respects.
MPI_count gives the opportunity to evade any such chaos, whether introduced by the standard or an implementation.
-- Jeff Squyres [email protected]