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From: Eli Zaretskii <eliz@gnu.org>
Newsgroups: gmane.emacs.devel
Subject: Re: Failing to GC killed buffers considered harmful
Date: Tue, 31 Mar 2020 17:09:32 +0300
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To: Stefan Monnier <monnier@iro.umontreal.ca>
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> From: Stefan Monnier <monnier@iro.umontreal.ca>
> Date: Mon, 30 Mar 2020 14:32:30 -0400
> Cc: Eli Zaretskii <eliz@gnu.org>, Daniel Colascione <dancol@dancol.org>,
>  emacs-devel@gnu.org
> 
> > FWIW, maybe we should get rid of all_buffers.
> > AFAICT the only reason we need it is to unmark the buffers during the
> > sweep phase, and we could allocate buffers like any other
> > pseudovector instead.
> 
> The patch below seems to work.
> 
> The only worrisome part I think is that `live_buffer_holding` allowed
> pointers into buffer objects, whereas `live_vector_p` only treats
> pointers to the beginning of the object as a valid reference.
> 
> Not sure why buffers would be more likely to have valid pointers into
> them (and can't remember discussions about that either)

Pointers to buffer text come to mind.

> -        if (!pdumper_object_p (buffer))
> -          XUNMARK_VECTOR (buffer);

Why is this part being removed?