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From: Jonathan Wakely <jwakely@redhat.com>
Date: Tue, 15 Jun 2021 22:33:33 +0100
Message-ID: <CACb0b4=Pb5JMezHcNBF7ZsTyAcDP4Nwcnk4mpBKgHpyBieuAXQ@mail.gmail.com>
Subject: Re: [committed] libstdc++: Make ranges CPOs final and not addressable
To: Tim Song <t.canens.cpp@gmail.com>
Cc: "libstdc++" <libstdc++@gcc.gnu.org>, gcc-patches <gcc-patches@gcc.gnu.org>
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On Tue, 15 Jun 2021 at 21:32, Tim Song wrote:
>
> CPOs are specified as actual semiregular function objects that can be
> copied and constructed freely, so it seems a bit hostile to make them
> final/non-addressable? (It's debatable whether the type of a CPO is a
> type "specified in the C++ standard library" for which [derivation]/4
> would apply.)

I noticed that libstdc++ was failing some libc++ tests, but that was
only for ranges::advance etc and not the CPOs. I guess I got a bit
carried away, and it shouldn't apply to the CPOs, only the
[range.iter.ops] "function templates" (which are not really function
templates).