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Subject: Re: [ub] Justification for < not being a total order on pointers?
From: Peter Sommerlad (peter.sommerlad_at_[hidden])
Date: 2013-10-17 03:38:16


Hi, just to throw in my 0.02 CHF:
On 17.10.2013, at 07:27, Nevin Liber <nevin_at_[hidden]> wrote:

> 3. Pointers, while historically not totally ordered, are practically so for all systems in existence today, with the exception of the ivory tower minds of the committee, so the point is moot.
Well, I dream the future with non-uniform memory architectures might make that argument wrong again. We might have "pointers" that differ substantially, depending if the memory address resides in RAM "directly" attached to a CPU or on a different CPU or on a GPU. And comparing such pointers wildly might not be the thing you should be allowed to do.

Just remember, technology development often goes in circles, e.g., we get electric cars again after 100+ years, we are reinventing parallel programming (a lot of work from the 70s/80s gets rediscovered), etc.

Regards
Peter.

-- 
Prof. Peter Sommerlad
Institut für Software: Bessere Software - Einfach, Schneller!
HSR Hochschule für Technik Rapperswil
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