add JDK 17 build

[SethTisue]

(...and drop 16, presumably)

JDK 17 is now feature-complete and the final release lands in September, so now is a good time for this

The current JDK 17 build is "Build 26 (2021/6/11)".

using #1352 as a guide to steps needed:

• on all 3 behemoths:
  • cd /usr/lib/jvm
  • sudo curl -O -L 'https://download.java.net/java/early_access/jdk17/26/GPL/openjdk-17-ea+26_linux-x64_bin.tar.gz'
  • sudo dtrx -n openjdk-17-ea+26_linux-x64_bin.tar.gz
  • sudo rm openjdk-17-ea+26_linux-x64_bin.tar.gz
  • sudo chmod -R go+rX openjdk-17-ea+26_linux-x64_bin
  • sudo ln -s openjdk-17-ea+26_linux-x64_bin java-17-openjdk-x64
  • ./java-17-openjdk-x64/jdk-17/bin/java -version
• add -jdk17- jobs (on 2.12.x and 2.13.x) with JDK version set appropriately
• make sure both jobs extract
• make sure both jobs have at least a green core
• update scripts/Report.scala (both branches)
• report selected failures upstream
• open a separate ticket on gradually getting more projects green?
• disable the old -jdk16- jobs
• delete the old -jdk16- workspace directories

[lrytz]

👍 thank you, this is the perfect time to start testing 17.

[fernandoracca]

this is great! looking forward to start using the newer JVMs.

[SethTisue]

2.13.x core is green. I will dig into the specific failures

2.12.x core fails with some lambda deserialization problem. I've opened a separate ticket on it: scala/bug#12419

[SethTisue]

Jason fixed the deserialization thing, so the 2.12.x core is now green too (on 2.12.15-bin-b2b8816)

[SethTisue]

2.13.x status as of this run: FAILURES (UNEXPECTED): akka-http,akka-more,macwire,classutil

all four repos are running afoul of https://openjdk.java.net/jeps/403, resulting in java.lang.reflect.InaccessibleObjectExceptions

I will mark them as expected-to-fail.

• macwire: notified maintainers: version bumps, then add JDK 11 and 17 to CI matrix softwaremill/macwire#162
• classutil: repo seems abandoned
• @patriknw heads up on the akka-http failure and the akka-more failure

I suspect it would be possible for me to make them pass by replacing --illegal-access=... with the more specific --add-opens, but in general, it's not a priority for us to get out ahead of upstream maintainers on JDK 17 support once the overall number of green projects seems adequate for QAing Scala itself.

[patriknw]

Thanks @SethTisue .
I have created issues akka/akka-http#3852 and akka/akka#30341

[SethTisue]

declaring victory here. we'll want to ship 2.12.15 before too much longer, in order to get the serialization fix out

[SethTisue]

2.12.15 planning thread: https://contributors.scala-lang.org/t/scala-2-12-15-planning/5152