bug#39482: 26.3; set-fontset-font with emacs charset does not work correctly

[Eli Zaretskii <eliz@gnu.org>]

> From: ynyaaa@gmail.com
> Cc: 39482@debbugs.gnu.org
> Date: Sat, 08 Feb 2020 11:27:53 +0900
> 
> I installed emacs-27.0.60-snapshot-emacs-27-2019-12-28-x86_64-installer.exe
> and tested the same form. It looks like there is no difference.

Are you using HarfBuzz?  I don't know if the installer installs the
HarfBuzz library by default.  If the library is not installed, Emacs
will fall back on Uniscribe, and you have the same problems as in
Emacs 26 again.  "C-u C-x =" on some character should tell you if
HarfBuzz or Uniscribe is being used.

> >>        (kr-spec '("BatangChe" . "ksc5601.1987"))
> 
> Replacing "ksc5601.1987" with "ksc5601.1987-0" makes most of
> 'korean-ksc5601 characters displayed with BatangChe font.
> (Some characters are displayed with SimHei.)
> 
> I think "ksc5601", "ksc5601*" or "ksc5601.1987" should be accepted.

IME, font families are not supported well on MS-Windows, and font
registry is an XLFD notion supported natively on X Windows that I
wouldn't be surprised if is not well supported on Windows, either.
That said, people who have enough time on their hands are welcome to
dig into the font/fontset support code on MS-Windows and suggest
patches to improve that.