After updating in the obvious way to tzdata2018a we have a test failure as follows:

Very likely due to changes to Ireland's time zones:

A colleague reports:

"Ireland will observe standard time during the summer and have a negative DST offset during the winter, an arrangement that has not been used before."

STDOUT:
Compiling tz files!
testing!
OLD.getZoneInfoOld()[1]=1279
OLD.getZoneInfoOld()[2]=661
OLD.getZoneInfoOld()[3]=600
OLD.getAvailableIDs()=4793, total=627
OLD.getAliasTable()=1322, total=227
OLD.TotalTZ()=289 (ms)
NEW.getTimeZone()[1]=4728
NEW.getTimeZone()[2]=440
NEW.getTimeZone()[3]=310
NEW.getAvailableIDs()=33, total=627
NEW.getAliasTable()=85, total=227
NEW.TotalTZ()=114 (ms)
******************************
Eire : Eire
    offset=3600000,dstSavings=3600000,useDaylight=true,transitions=228,offsets=6,checksum=1280024022,gmtChanged=false
[NG]offset=3600000,dstSavings=0,useDaylight=true,transitions=228,offsets=6,checksum=1280024022,gmtChanged=false
    -------------
    SimpleTimeZone (NG)
       stz=java.util.SimpleTimeZone[id=Eire,offset=3600000,dstSavings=3600000,useDaylight=true,startYear=0,startMode=2,startMonth=2,startDay=-1,startDayOfWeek=1,startTime=3600000,startTimeMode=2,endMode=2,endMonth=9,endDay=-1,endDayOfWeek=1,endTime=3600000,endTimeMode=2]
      stz0=null
    -------------
STDERR:
javazic: warning: found last rules for Eire inconsistent.
java.lang.RuntimeException: FAILED: Eire
at TestZoneInfo310.main(TestZoneInfo310.java:174)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at com.sun.javatest.regtest.agent.MainActionHelper$SameVMRunnable.run(MainActionHelper.java:229)
at java.lang.Thread.run(Thread.java:745)