bug#30364: 26.0.91; thread crash on macos

[Eli Zaretskii]

> Cc: Andreas Schwab <schwab@linux-m68k.org>,
>  Noam Postavsky <npostavs@gmail.com>, 30364@debbugs.gnu.org,
>  Noam Postavsky <npostavs@users.sourceforge.net>, Alan Third <alan@idiocy.org>
> From: Paul Eggert <eggert@cs.ucla.edu>
> Date: Wed, 28 Feb 2018 11:15:12 -0800
> 
> On 02/28/2018 10:07 AM, Aaron Jensen wrote:
> > Attached. AFAICT sys_create_thread is only used by make-thread.
> 
> This patch looks OK to me, to be applied to the emacs-26 branch (not 
> master).

I agree.  (The master branch already has a better fix.)