/etc/fonts/fonts.conf is required even when using FONTCONFIG_SYSROOT
I am running a small program that essentially calls
FcFini() with a custom
fonts.conf to cache some fonts into a separate directory.
It's running on a system that does not ship
/etc/fonts/fonts.conf by default (the defaults are read from
/usr/share/defaults/fonts/fonts.conf), but I do set
FONTCONFIG_SYSROOT for my custom
fonts.conf to be used.
This should work, but
FcConfigFilename(), which tries to load
/etc/fonts/fonts.conf, fails and lead
_FcConfigParse() to bail out early before calling
FcConfigRealFilename() (which should have worked because of