[Fontconfig] Next steps for a reproducible Fontconfig?

[Akira TAGOH]

On Sun, Jan 13, 2019 at 8:53 PM Alexander Larsson
<alexander.larsson at gmail.com> wrote:
> Yes:ish. It should not *normally* happen. But you may run into it in
> uncommon situations like e.g. chrome using a statically linked version
> of fontconfig that has a different fontconfig cache format.
>
> > > However, flatpak will never parse the entire xml fontconfig file
> > > format (which isn't even really stable over time), so such a config
> > > would have to be external in a simpler config format.
> >
> > The fontconfig xml format is quite stable and is designed to be
> > manipulated by tools that do not understand the full contents, hence
> > using XML and providing a suitable DTD.
>
> We recently ran into issues with fontconfig xml parsing errors in chrome
> when using config files from a newer host fontconfig that were not
> parsable by the statically linked chrome copy, so it is not perfect.

Right. that is really a pain in the neck. not adding new syntax is
hard to improve and grow. that said, just ignoring unknown syntax
would makes harder to find an error. we may need to think about
measures for that like checking a version of config and library say,
but anyway.

-- 
Akira TAGOH