Hi all, @Ran When I created this discussion thread, the latest available version of Scala 2.12 was 2.12.15. I don't see 2.12.16 being released yet, only discussed. I did read that they were planning it in the last couple of weeks but haven't seen any progress since. Do you know more about the timeline?
I would also like to make a final call towards Scala users to provide their input in the next 72 hours. Else, I'll open up a voting thread to make the upgrade. Best regards, Martijn Op vr 20 mei 2022 om 14:10 schreef Ran Tao <chucheng...@gmail.com>: > Got it. But I think the runtime java environment e.g. jdk11 env may cannot > optimize these scala lower bytecode very well. However currently no direct > report show this problem. hah~ > > Chesnay Schepler <ches...@apache.org>于2022年5月20日 周五19:53写道: > > > It's not necessarily required that the scala byte code matches the > > version of the java byte code. > > > > By and large such inconsistencies are inevitable w.r.t. external > libraries. > > > > On 20/05/2022 12:23, Ran Tao wrote: > > > Hi, Martijn. Even if we upgrade scala to 2.12.15 to support Java17, it > > just > > > fix the compilation of FLINK-25000 > > > <https://issues.apache.org/jira/browse/FLINK-25000> . There is > another > > > problem[1] that Scala <=2.13 can't generate jvm11 or higher bytecode > > > version. The flink project target class bytecode version is > inconsistent > > > between scala and java source. > > > If we decide to upgrade scala version, how aboout scala 2.12.16, as i > > know > > > from scala community, the 2.12.16 will backport 2.13 functionilies like > > > jvm11,jvm17 target jvm class support. > > > > > > [1] https://issues.apache.org/jira/browse/FLINK-27549 > > > > > > Martijn Visser <martijnvis...@apache.org> 于2022年5月20日周五 16:37写道: > > > > > >> Hi everyone, > > >> > > >> I would like to get some opinions from our Scala users, therefore I'm > > also > > >> looping in the user mailing list. > > >> > > >> Flink currently is tied to Scala 2.12.7. As outlined in FLINK-12461 > [1] > > >> there is a binary incompatibility introduced by Scala 2.12.8, which > > >> currently limits Flink from upgrading to a later Scala 2.12 version. > > >> According to the Scala 2.12.8 release notes, "The fix is not binary > > >> compatible: the 2.12.8 compiler omits certain methods that are > > generated by > > >> earlier 2.12 compilers. However, we believe that these methods are > never > > >> used and existing compiled code will continue to work" > > >> > > >> We could still consider upgrading to a later Scala 2.12 version, the > > latest > > >> one currently being 2.12.15. Next to any benefits that are introduced > in > > >> the newer Scala versions, it would also resolve a blocker for Flink to > > add > > >> support for Java 17 [2]. > > >> > > >> My question to Scala users of Flink and others who have an opinion on > > this: > > >> * Has any of you already manually compiled Flink with Scala 2.12.8 or > > >> later? > > >> * If so, have you experienced any problems with checkpoint and/or > > savepoint > > >> incompatibility? > > >> * Would you prefer Flink breaking binary compatibility by upgrading > to a > > >> later Scala 2.12 version or would you prefer Flink to stick with Scala > > >> 2.12.7? > > >> > > >> Note: I know there are also questions about Scala 2.13 and Scala 3 > > support > > >> in Flink; I think that deserves its own discussion thread. > > >> > > >> Best regards, > > >> > > >> Martijn Visser > > >> https://twitter.com/MartijnVisser82 > > >> https://github.com/MartijnVisser > > >> > > >> [1] https://issues.apache.org/jira/browse/FLINK-12461 > > >> [2] https://issues.apache.org/jira/browse/FLINK-25000 > > >> > > > > > > > -- > Best, > Ran Tao >