bug#33729: 27.0.50; Partial glyphs not rendered for Gujarati with Harfbuzz enabled (renders fine using m17n)

[Eli Zaretskii]

> From: Kaushal Modi <kaushal.modi@gmail.com>
> Date: Thu, 13 Dec 2018 15:43:50 -0500
> Cc: behdad@behdad.org, 33729@debbugs.gnu.org, far.nasiri.m@gmail.com
> 
>  For debugging the such rendering differences, the actual font used by
>  Emacs for a given part of the text need to be known,
> 
> I am using Mukta Vaani font for Gujarati. It is a free font and be downloaded 
> from
> https://ektype.in/mukta-vaani.html.

Your data indicates that the m17n build performs character composition
at buffer position 34, whereas the harfbuzz build does not.  The
question is why.