Re: Heads-up: Emacs 26.1 RC1

[Eric Abrahamsen <eric@ericabrahamsen.net>]

On 03/20/18 11:18 AM, Eli Zaretskii wrote:
>> From: Eric Abrahamsen <eric@ericabrahamsen.net>
>> Cc: pierre.techoueyres@free.fr,  johnw@gnu.org,  emacs-devel@gnu.org
>> Date: Tue, 20 Mar 2018 16:25:04 +0800
>> 
>> > The changes in error/warning messages and in the test suite are okay
>> > to go, but I'm worried by the 2 changes that add a condition (where
>> > you went from (when ...) to (cond ...)).  Is this really necessary,
>> > and what problems do they solve?
>> 
>> I know... Mostly it took so long because of testing. The test suite
>> changes are there to test the new code, which directly models errors
>> currently in the wild, and they can't go in by themselves.
>> 
>> Very long story short, in Emacs 26 eieio objects went from being defined
>> as vectors to being defined as objects. This messed up how they are
>> serialized to disk using eieio-persistent. Two main consumers of
>> eieio-persistent (pcache and the Gnus registry) are currently broken
>> because of this. The `cond' statement is there to make sure that, in
>> these two packages, the objects are written correctly to disk.
>
> Which code/packages outside of CEDET use the affected functions?

Pcache is a big one, as several other packages depend on it -- though I
haven't been able to figure out exactly how many from the Melpa repo. It
currently errors loudly. The Gnus repository is another, and it is
silently corrupted. Those are the main two, and the code changes (though
they look large) are specifically targeted at those two packages. A more
general solution is in the works for 27, but this was the smallest diff
I could manage that fixes the problem.