[mpiwg-rma] same_op_no_op

[Balaji, Pavan]

On Mar 13, 2014, at 4:08 PM, Jeff Hammond <jeff.science at gmail.com> wrote:
>> It was not disallowed in MPI-2.  I meant that we made a mistake in MPI-3 to disallow it since that is not backward compatible.
> 
> You told me two days ago it was at best undefined, which is no more
> useful than disallowed:

I’m not sure what you are referring to, but that was no my intention.  Perhaps I misunderstood what you were asking.

It think it’s pretty clear that it’s disallowed in MPI-3, not undefined.

>> IMO, we should have kept the same semantics as MPI-2, but allowed the user to relax it with info arguments.
> 
> Well we broke backwards compatibility but made it almost impossible
> for anyone to notice and certainly didn't add an advice to users so we
> are clearly all jerks.

I like MPI-2’s approach.  The data content is undefined, but not an error.

  — Pavan