[HarfBuzz] Failure in hb_font_get_nominal_glyph

[Eli Zaretskii]

Could someone please take a look at the problems described here:

  https://lists.gnu.org/archive/html/emacs-devel/2019-07/msg00540.html
  https://lists.gnu.org/archive/html/emacs-devel/2019-07/msg00557.html
  https://lists.gnu.org/archive/html/emacs-devel/2019-07/msg00558.html
  https://lists.gnu.org/archive/html/emacs-devel/2019-07/msg00561.html

and tell whether it is expected that HarfBuzz 1.7.5 is too old to
support hb_font_get_nominal_glyph reliably on MS-Windows?  According
to the HarfBuzz docs, that function is available since v1.2.3.

Or maybe the code we have in Emacs has a bug?  If you want to have a
look at the code that fails, it is here:

  http://git.savannah.gnu.org/cgit/emacs.git/tree/src/w32uniscribe.c#n1328

In a nutshell, the question is: why would hb_font_get_nominal_glyph
fail for the Courier New font, even when we are requesting a glyph for
an ASCII character?

TIA