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Re: [ub] Justification for < not being a total order on pointers?

From: Lawrence Crowl <Lawrence_at_[hidden]>
Date: Thu, 10 Oct 2013 14:32:41 -0700
On 10/10/13, Gabriel Dos Reis <gdr_at_[hidden]> wrote:
> | At this point, I think we need to ask if we really do want to support machines
> | with small segments. Does anyone know of any current such machines?
> That is a good question that we should consider.
> Another aspect to consider is that, even though this restriction
> was originally motivated by segmented architecture, it is also useful
> for other things and implementation techniques (including compacting
> GCs). One question is whether we believe we want to forgo implementations
> or implementation techniques that might profit from the current
> restriction.

Wouldn't compacting GCs fall afoul of the existing std::less problem?
I mean, we could still have an std::less that imposed a total order, but
that order might change during execution, and I could see that causing
some difficulties with unordered maps. :-)

> I think this question should be considered independently of whether we
> still want to support segmented architectures, because that may affect
> the form of the outcome.

Lawrence Crowl

Received on 2013-10-10 23:32:42