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Subject: Re: [OMPI users] Help: OpenMPI Compilation in Raspberry Pi
From: Jeff Squyres (jsquyres) (jsquyres_at_[hidden])
Date: 2013-01-17 16:28:12


On Jan 16, 2013, at 6:41 AM, Leif Lindholm <Leif.Lindholm_at_[hidden]> wrote:

> That isn't, technically speaking, correct for the Raspberry Pi - but it is a workaround if you know you will never actually use the asm implementations of the atomics, but only the inline C ones..
>
> This sort of hides the problem that the dedicated barrier instructions were not available in ARMv6 (it used "system control coprocessor operations" instead.
>
> If you ever executed the asm implementation, you would trigger an undefined instruction exception on the Pi.

Hah; sweet. Ok.

So what's the right answer? Would it be acceptable to use a no-op for this operation on such architectures?

-- 
Jeff Squyres
jsquyres_at_[hidden]
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