Hi Luigi,
here on Debian we got a bug report that luatex cannot build formats
under a broken locale. I can reproduce this on standard TeX Live, too:
$ LC_TIME=en_DE.UTF-8 luatex -ini -jobname=luatex -progname=luatex luatex.ini
Unable to read environment locale: exit now.
$
(same on dev version)
It comes from the code of luainit
env_locale = setlocale (LC_ALL, "");
if (!env_locale && !lua_only) {
fprintf(stderr,"Unable to read environment locale: exit now.\n");
exit(1);
}
I agree that the locale is completely broken, and the system does not
support this locale.
BUT it would be nice if luatex would not crash on such a setup, at least
during format build?
WDYT?
It's not a bug, luatex wants a sane locale --- building a format or not, it doesn't matter.
We can change it, but for sure not for texlive 2019.