bug#30193: crash in libotf

[handa]

In article <xqpo60gcf4.fsf@fencepost.gnu.org>, Glenn Morris <rgm@gnu.org> 
writes:
> Thanks, works for me.

Thank you for confirming that!

> Can anything be done to mitigate this in Emacs?
> I expect it will be some time before the fixed libotf becomes the default
> in some G/L distributions. Till then, an email can crash Emacs (I
> assume) for someone who uses it to read mail.

At the moment, this problem occurs with NotoSerifKannada-Regular.ttf
and NotoSerifKannada-Bold.ttf. So, adding the following code will save
Emacs from crashing.

1. Check the version number of libotf in configure script.
2. Expose that version number to config.h.
3. In xfaces.c, if the version number is less than 0.9.16, initialize
   Vface_ignored_fonts to ("Noto Serif Kannada").

> Can there at least be a PROBLEMS entry?

We can advise (push "Noto Serif Kannada" face-ignored-fonts).

> Does this relate to bug#27836, 28110 at all?

#28110 is surely because of this bug, but as I can't reproduce #27836,
I'm not sure about it.

---
K. Handa
handa@gnu.org