Eli Zaretskii <eliz@gnu.org> writes:

> I think I figured it out.  It seems to be a cockpit error: the
> "Medium" part is not part of the :family, and you already say
> ":weight medium" in the attributes anyway.  Try this instead:
>
>  '(default ((t (:family "Source Code Pro" :foundry "outline" :slant
> normal :weight medium :height 90 :width normal))))
>
> With this, I get the same results as with an older Emacs.  It is true
> that the older Emacs also accepted "Source Code Pro Medium" as the
> family, but the result was that it loaded the same font as the master
> branch without "Medium".
>
> Does this resolve your issue?

No, it doesn't.  I updated my local git repo and built a fresh Emacs.
I'm comparing New (6c9ac53249) with Old (41b1fa05c7).

With  '(default ((t (:family "Source Code Pro Medium" :foundry "outline" :slant normal :weight medium :height 90 :width normal))))

- Old uses Source Code Pro Medium font (good)
- New uses Arial (bad)

 With '(default ((t (:family "Source Code Pro" :foundry "outline" :slant normal :weight medium :height 90 :width normal))))

- Old uses Source Code Regular font (bad)
- New uses Source Code Regular font (bad)

I'm attaching two snapshots where you can hopefully see the difference.
This is the medium font: