bug#17168: 24.3.50; Segfault at mark_object

[Eli Zaretskii <eliz@gnu.org>]

> Date: Sun, 06 Apr 2014 08:59:55 -0700
> From: Daniel Colascione <dancol@dancol.org>
> CC: dmantipov@yandex.ru, 17168@debbugs.gnu.org
> 
> > As an alternative, would it make sense to try to understand why the
> > problems started when they did?  IOW, how come we never saw this until
> > now?
> 
> Who knows? The problem arises we happen to form a pointer on the stack
> to an undead symbol, and *any* code change could be responsible for our
> doing that more frequently. I don't see you can blame it on 114156.

Then how do you explain that we never saw such problems, in all the
years before?

> > In http://debbugs.gnu.org/cgi/bugreport.cgi?bug=15583#23, Richard
> > provided the last good revno (113938) and the first bad one (114268);
> > I looked at that range of revisions, and 114156 looks relevant.  How
> > about if we revert it and see if the problems go away?
> 
> The bug would still be there, and we'd have no way to tell whether your
> proposed change actually reduced its occurrence to a tolerable level.
> Why would you want to do that instead of just fixing the bug?

Because it's simpler, and because it just might be that the bug was
caused by that other changeset.