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Subject: Re: [OMPI users] EXTERNAL: Re: How could OpenMPI (or MVAPICH) affect floating-point results?
From: Tim Prince (n8tm_at_[hidden])
Date: 2011-09-20 11:36:27

On 9/20/2011 10:50 AM, Blosch, Edwin L wrote:

> It appears to be a side effect of linkage that is able to change a compute-only routine's answers.
> I have assumed that max/sqrt/tiny/abs might be replaced, but some other kind of corruption may be going on.

Those intrinsics have direct instruction set translations which
shouldn't vary from -O1 on up nor with linkage options nor be affected
by MPI or insertion of WRITEs.

Tim Prince