Sure, my workaround will be broken if CLDR project decides just to swap standard/daylight names but this will also break the main consumers of CLDR data, namely ICU and OpenJDK (at least current and past versions of actual software distributions). I cannot imagine that this is a serious way to go since (what I have understood until now) your team value backwards compatibility a lot.

> Meno Hochschild wrote:
> > I have adjusted my tzdb-compiler (Time4J) such that it looks if
> all rule lines
> > referencing the same name (here: Eire) contain any negative dst
> offsets. If yes
> > then let's assume summer time for SAVE=0 and winter time for SAVE
> < 0. So I can
> > still work with old unchanged CLDR-entries for getting "Irish
> Standard Time" in
> > summer.
>
> This sounds like a good idea regardless of whether we make changes
> to zic input.
> Couldn't OpenJDK do the same?  I'm somewhat leery of changing zic
> input format
> to address this problem, particularly if a simpler workaround is available.
>

I'm also not sure any changes in zic input format are necessary.

BTW, what Meno explained above is exactly what we're worrying about.
If CLDR project decides to swap standard/daylight names at some point,
Meno's code will be broken. His code is not affected even saving amount
is negative, but it's still sensitive to how CLDR identifies Irish
Standard Time.

-Yoshito