Open MPI logo

Open MPI User's Mailing List Archives

  |   Home   |   Support   |   FAQ   |  

This web mail archive is frozen.

This page is part of a frozen web archive of this mailing list.

You can still navigate around this archive, but know that no new mails have been added to it since July of 2016.

Click here to be taken to the new web archives of this list; it includes all the mails that are in this frozen archive plus all new mails that have been sent to the list since it was migrated to the new archives.

Subject: Re: [OMPI users] EXTERNAL: Re: MPI_GET beyond 2 GB displacement
From: Jed Brown (jed_at_[hidden])
Date: 2010-07-07 18:07:49


On Wed, 07 Jul 2010 15:51:41 -0600, "Price, Brian M (N-KCI)" <brian.m.price_at_[hidden]> wrote:
> Jeff,
>
> I understand what you've said about 32-bit signed INTs, but in my program, the displacement variable that I use for the MPI_GET call is a 64-bit INT (KIND = 8).

The MPI Fortran bindings expect a standard int, your program is only
working because your system is little endian so the first 4 bytes are
the low bytes (correct for numbers less than 2^31), it would be
completely broken on a big endian system. This is a library issue, you
can't fix it by using different sized ints in your program and you would
see compiler errors due to the type mismatch if you were using Fortran
90 (which is capable of some type checking).

Jed