bug#16731: 24.3.50; Latin small letter sharp s is not considered lower-case

[Andreas Röhler]

Am 12.02.2014 20:49, schrieb Eli Zaretskii:
> > Date: Wed, 12 Feb 2014 20:31:20 +0100
> > From: Andreas Röhler <andreas.roehler@easy-emacs.de>
> >
> > > See http://debbugs.gnu.org/10576
> > >
> > > (I have no idea whether this is an Emacs bug or not.)
> >
> > IMO the answer given at link is not valid.
>
> It accurately describes what happens in the code, so it's definitely
> valid.
>
> > When seeing there is a downcase-table, the check probably should be done 
> > against this.
>
> Not sure what you mean by that, please elaborate.

See buffer.h
IIUC the mentioned lowercasep is implemented as !uppercasep (c) && upcase1 (c) 
!= c;
upcase1 (c) must fail, as there is no upcased of this char.

While upcase1 can't succeed, downcase should - if "ß" is a member of 
downcase_table.