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From: Tim Song <t.canens.cpp@gmail.com>
To: Patrick Palka <ppalka@redhat.com>
Cc: gcc-patches <gcc-patches@gcc.gnu.org>,
	"libstdc++" <libstdc++@gcc.gnu.org>
Subject: Re: [PATCH] libstdc++: Fix iterator caching inside range adaptors [PR100479]
Date: Mon, 17 May 2021 13:39:51 -0500	[thread overview]
Message-ID: <CAPQZVxuZPX+LGwcO1W2D+E_g_O2gk9au+-ywB5G_Ntq4NyiEjg@mail.gmail.com> (raw)
In-Reply-To: <20210517154302.840608-1-ppalka@redhat.com>

On Mon, May 17, 2021 at 11:46 AM Patrick Palka via Libstdc++
<libstdc++@gcc.gnu.org> wrote:
>         constexpr void
>         _M_set(const _Range&, const iterator_t<_Range>& __it)
>         {
>           __glibcxx_assert(!_M_has_value());
> -         _M_iter = __it;
> +         this->_M_payload._M_payload._M_value = __it;
> +         this->_M_payload._M_engaged = true;
>         }
>        };

This part looks questionable - if we don't have a value then we can't
assign to a nonexistent object.

Also, I believe the offset partial specialization of _CachedPosition
needs a change to invalidate the source on move.

  parent reply	other threads:[~2021-05-17 18:40 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-05-17 15:43 Patrick Palka
2021-05-17 16:51 ` Jonathan Wakely
2021-05-17 18:39 ` Tim Song [this message]
2021-05-17 19:59   ` Patrick Palka
2021-05-17 22:28     ` Tim Song
2021-05-18  4:53       ` Patrick Palka
2021-05-24 18:59         ` Jonathan Wakely

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