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Date: Mon, 24 May 2021 19:59:50 +0100
From: Jonathan Wakely <jwakely@redhat.com>
To: Patrick Palka <ppalka@redhat.com>
Cc: Tim Song <t.canens.cpp@gmail.com>, libstdc++ <libstdc++@gcc.gnu.org>,
 gcc-patches <gcc-patches@gcc.gnu.org>
Subject: Re: [PATCH] libstdc++: Fix iterator caching inside range adaptors
 [PR100479]
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On 18/05/21 00:53 -0400, Patrick Palka via Libstdc++ wrote:
>On Mon, 17 May 2021, Tim Song wrote:
>
>> On Mon, May 17, 2021 at 2:59 PM Patrick Palka <ppalka@redhat.com> wrote:
>> >
>> > +       constexpr _CachedPosition&
>> > +       operator=(_CachedPosition&& __other) noexcept
>> > +       {
>> > +         if (std::__addressof(__other) != this)
>>
>> I don't think we need this check - self-move-assigning the underlying
>> view isn't required to be a no-op, so we should still invalidate.
>
>Sounds good, so like so:

Looks good to me (but then so did the previous one ;-)

Please push, as this is an improvement on what's on trunk now. If Tim
spots any more problems they can be fixed later.


Thanks both of you.