On Jul 16, 2013, at 22:29 , Jeff Squyres (jsquyres) <jsquy...@cisco.com> wrote:
> On Jul 16, 2013, at 4:22 PM, George Bosilca <bosi...@icl.utk.edu> wrote: > >> Btw, I have a question to you fellow MPI Forum attendees. I just can't >> remember why the MPI forum felt there was a need for the >> MPI_Type_get[_true]_extent_x? MPI_Count can't be bigger than MPI_Aint, > > Yes, it can -- it has to be the largest integer type (i.e., it even has to be > able to handle an MPI_Offset). Technicalities! In the entire standard MPI_Offset is only used to access files, not to build datatypes. As such there is no way to have the extent of an datatype bigger than MPI_Aint. Thus, these accessors returning MPI_Count are a useless overkill, as they cannot offer more precision that what the version returning MPI_Aint is already offering. George. PS: I hope nobody has the idea to define the MPI_Offset as a signed type … >> so I don't see what is the benefit of extending the >> MPI_Type_get_true_extent(MPI_Datatype, MPI_Aint*, MPI_Aint*) and >> MPI_Type_get_extent(MPI_Datatype, MPI_Aint*, MPI_Aint*) with the >> corresponding _X versions? > > > -- > Jeff Squyres > jsquy...@cisco.com > For corporate legal information go to: > http://www.cisco.com/web/about/doing_business/legal/cri/ > > > _______________________________________________ > devel mailing list > de...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/devel
