Thank you for taking the time to report this bug and helping to make Ubuntu better.
The changes come from the update to tzdata2019c [1] which was done at a later time in OpenJDK 11 - in fact the newer OpenJDK 11.0.6 reports the same results as OpenJDK 8u232. OpenJDK 11.0.6 is available in focal- proposed as of now and will available in supported Ubuntu releases soon. The announcement for tzdata2019c [2] does state that past timestamps for Turkey changed and the OpenJDK commit [1] has the references to the changes. To check if OpenJDK itself was somehow incorrectly interpreting the data I also run the following using 'date' which uses the system's timezone data (also sourced from tzdata2019c). Results matches the OpenJDK output: $ date --date='TZ="Europe/Istanbul" 1943-01-01 12:01:01' '+%s' -852044339 Please note that date is limited to 'seconds' precision for the epoch. If that is somehow wrong, it should be brought to the attention of the maintainers of tzdata through the t...@iana.org mailing list as stated in [3]. I'm closing this bug now. References: [1] https://hg.openjdk.java.net/jdk8u/jdk8u-dev/jdk/rev/8560bc534080#l4.130 [2] https://mm.icann.org/pipermail/tz-announce/2019-September/000057.html [3] https://www.iana.org/time-zones ** Changed in: openjdk-8 (Ubuntu) Status: Confirmed => Invalid -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1859217 Title: openjdk8 update 8u232-b09-0ubuntu1~18.04.1 breaks Timestamp values for timezones that change DST observance To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/openjdk-8/+bug/1859217/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs