bug#57555: 29.0.50; variable-pitch font issue with medium weight default font

[Eli Zaretskii]

> From: Amin Bandali <bandali@gnu.org>
> Cc: 57555@debbugs.gnu.org
> Date: Mon, 05 Sep 2022 14:19:14 -0400
> 
> > Even if you set the face's font explicitly by its full XLFD name, not
> > implicitly via :family?
> >
> 
> Ha, so I just tried with the following XLFD:
> 
>     (set-face-font 'variable-pitch
>                    "-GNU -FreeSans-*-*-*-*-14-*-*-*-*-0-iso10646-1")
> 
> And it works, somewhat.  Emacs now uses GNU FreeSans, but seemingly
> only its regular variant.  Based on the '*' I specified for the third
> and fourth fields (WEIGHT_NAME and SLANT), I would expect it to pick
> GNU FreeSans's other variants (bold, oblique, or bold oblique) where
> needed, but it doesn't seem to.

No, it can't: you specified a particular font.  The requirement
regarding the slant variant wasn't in your original complaint ;-)

Anyway, feel free to step through font_load_for_lface and its
subroutines, to figure out why your FreeSans font is rejected for
variable-pitch face.  Maybe you will find something that could be
improved there.