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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