bug#40987: 26.3; segfault with small nonascii file

[Eli Zaretskii]

> From: Sanjoy Mahajan <sanjoy@mit.edu>
> Date: Thu, 30 Apr 2020 15:31:37 -0400
> 
> Visting the file trigger_bug_in_emacs.txt attached below causes emacs to
> segfault.  The short version info: Debian/GNU Linux x86_64, unstable,
> which provides Debian's Emacs package version 26.3+1-1.
> 
> The recipe is:
> 
>   emacs -Q trigger_bug_in_emacs.txt
> 
> To get debugging output, I ran it under gdb using the .gdbinit from the
> Emacs git repo and logged the output of 'bt full' and 'xbacktrace'.
> Their outputs are in the attached gdb.txt.  Warning: Visiting the
> gdb.txt file will also crash emacs!

Could you try the latest pretest of Emacs 27, available from
alpha.gnu.org?  I think this problem is already fixed there.

Thanks.