Re: master 6ed1994d27: Prevent crashes from illegal locale coding systems

[Po Lu]

Eli Zaretskii <eliz@gnu.org> writes:

> First, we don't use "illegal" in these cases, we use "invalid":
> there's nothing against any law in using bad values of some variables.

Okay, thanks.  I'll keep that in mind in the future.

> More importantly, why punting in these cases is the best possible
> solution? why not fall back to some reasonable encoding instead?

I think that if the locale coding system is set to an invalid value,
then the user probably knows there is a need to set it to something
other than the default value, but made a typo somewhere.

Decoding multibyte X keyboard input and XIM pre-edit text with any
coding system other than the actual locale coding system will result in
nonsensical text.

Maybe the best thing to do would be to log a message stating that the
specified coding system is invalid.

> And how come locale-coding-system is not a valid coding-system there
> in the first place?

The user could have set it to an invalid value, which leads to
spectacular crashes when setup_coding_system signals inside a GTK event
filter.

Thanks.