[tz] OpenJDK/CLDR/ICU/Joda issues with Ireland change

Paul Eggert eggert at cs.ucla.edu
Fri Jan 26 22:25:45 UTC 2018

On 01/26/2018 02:15 PM, Meno Hochschild wrote:
> Let's imagine that Ireland will one day start to consider the winter 
> time as standard and rename both winter and summer time accordingly. 
> Would the tzdb maintainers then "reuse" the "Eire"-rules for the new 
> positive dst offset? I hope not and ask if a new ruleset with a 
> different new name can be taken into consideration. Can I rely on that?

I'm afraid not, as that restriction is not in the code or the 
documentation. Also, I don't see why the restriction would help; it 
seems a bit arbitrary.

> By the way: I discovered that the current practice in Java is broken 
> for Ireland in the years 1968-71 where OpenJDK just prints "Greenwich 
> Mean Time" althoug it should be read as "Irish Standard Time". My 
> adjusted tz-compiler has finally coped with the right naming using the 
> version v2018b but would be broken again with new version v2018c (and 
> Java remains broken here for the years 1968-71 in Ireland). So the 
> reverted change in v2018c is not really an improvement (and for me 
> even worse).

Yes, sorry about that. I'm hoping to come up with a scheme that will 
support both old-style (2017c and earlier) and new-style (2018a and 
2018b) approaches soon. As usual I'll publish proposed patches before 
distributing a new release, and I hope you'll try them out.

> The new version v2018c is only good for OpenJDK when handling Ireland 
> now in year 2018. 

Yes, this is a known issue with CLDR, discussed here:


which says that CLDR doesn't worry about timestamps before 1990.

More information about the tz mailing list