Re: changed dlopen flags in dynlib.c, gccemacs crash

[Eli Zaretskii]

> From: Andrea Corallo <akrl@sdf.org>
> Cc: hx <silent2600@gmail.com>, emacs-devel@gnu.org
> Date: Thu, 09 Dec 2021 10:53:57 +0000
> 
> > Andrea, any better ideas?  I don't understand the reason for the
> > crash, as we seem to have defenses against this in Fnative_elisp_load,
> > so I'm probably missing something.
> 
> Hello all,
> 
> I'm no expert on 'dlopen' so I'm not sure about the impact of using
> RTLD_GLOBAL.  But should be noted that .eln files do share a number of
> symbol names, I'm wondering if this could be somehow problematic when
> using RTLD_GLOBAL, that's my suspect here.

Assuming the RTLD_GLOBAL flag was added.

But still, the crash is because we assume a Lisp object is a cons cell
and take its CDR.  So evidently it isn't a cons cell (probably nil),
and I don't understand how that could be caused, not even if
RTLD_GLOBAL was used.