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

[Eli Zaretskii]

> From: Philipp Stephani <p.stephani2@gmail.com>
> Date: Sun, 6 Mar 2022 15:32:14 +0100
> Cc: Eli Zaretskii <eliz@gnu.org>, hx <silent2600@gmail.com>, 
>       Emacs developers <emacs-devel@gnu.org>
> 
> > yes, I think once we have verified the issue is what we suspect we could
> > dlopen eln files as before and have RTLD_GLOBAL added for the other
> > cases.
> 
> This thread is already quite old, but let me point out that
> https://www.akkadia.org/drepper/dsohowto.pdf warns very strongly
> against using RTLD_GLOBAL (section 1.5.4), and I don't see a strong
> reason to not heed that warning. So I'd recommend removing RTLD_GLOBAL
> again.

We added it for a reason, and I don't see anything in Ulrich Drepper's
paper that could affect Emacs modules badly enough to back up on this.

That said, I don't see myself an expert on this stuff, so if enough
people here think it will have adverse effect on Emacs, I'm okay with
removing that flag, provided that we see some detailed explanations of
how this could be detrimental to use of Emacs modules.