bug#59715: 28.2; Emacs crashes after ``turkish-case-conversion-enable''

[Eli Zaretskii <eliz@gnu.org>]

> From: YUSUF ALPER ÇIKIŞIR
>  <yusufcikisir@std.iyte.edu.tr>
> Cc: 59715@debbugs.gnu.org
> Date: Sun, 04 Dec 2022 01:09:05 +0300
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> > Next, please run Emacs under GDB like this:
> >
> >   $ gdb /path/to/emacs
> >   ...
> >   (gdb) break xfaces.c:5847
> >   (gdb) run
> 
> GDB says: "No symbol table is loaded.  Use the "file" command."

The "/path/to/emacs" part was supposed to be the full absolute name of the
Emacs executable.  Was it?

> GNU Guix doesn't suit the FHS.  Maybe this is why GDB couldn't find the
> symbol table, and I don't know how to present it.  Maybe you can help me
> with that.

Sorry, I have no idea what Guix does and how it organizes the installation
tree.  Maybe someone else does.

> I compiled emacs-28.2 on a separate directory and ran that emacs binary
> under GDB.  But now I couldn't reproduce the problem because after the
> "run" command, Emacs never showed up.  Instead, it encountered the
> breakpoint immediately.
> 
> (gdb) break xfaces.c:5847
> Breakpoint 1 at 0x4d8725: file xfaces.c, line 5850.

Note that you said "xfaces.c:5847", but the breakpoint was set on line 5850
instead, which is a different source line.  This is why the breakpoint
breaks immediately at startup.

I believe the problem is that you built Emacs with optimizations.  Please
reconfigure it with

  $ CFLAGS='-O0 -g3' ./configure

and rebuild, then try again with the breakpoint at line 5847 of xfaces.c.
That breakpoint is supposed to break only if Emacs is about to crash by
calling emacs_abort.

> Guix doesn't have any site-init.el, but it had some patches.  I removed
> them but it's still the same.  I compiled vanilla emacs-28.2 as I said.
> It happens anyway.  I discovered that when I change the default
> monospace font to DejaVu Sans Mono, it stopped happening.  The crash was
> probably related to my font choice.  But how could that be?  That font
> didn't lack of any Turkish characters.
> 
> I was using this font:
> https://git.sr.ht/~protesilaos/iosevka-comfy

So the problem happens with the Iosevka font used as the default face's
font, is that right?

Anyway, please do try to produce the data from GDB I asked, with the
problematic font.