Dotty exception starting in JDK21-b21

[ericcaspole]

Starting in JDK-21-b21, due to this fix https://bugs.openjdk.org/browse/JDK-8292275 Dotty fails to run in 0.14.1. and 0.14.2.

I don't know much about Scala or Dotty, thanks for your analysis.

jdks/21-b21/Contents/Home/bin/java -jar renaissance-jmh-0.14.2.jar Dotty -t 1 -i 15 -wi 75 -f 1
# JMH version: 1.34
# VM version: JDK 21-ea, Java HotSpot(TM) 64-Bit Server VM, 21-ea+21-LTS-1778
# VM invoker: /Users/ecaspole/dev/opt/brunte/jdks/21-b21/Contents/Home/bin/java
# VM options: <none>
# Blackhole mode: compiler (auto-detected, use -Djmh.blackhole.autoDetect=false to disable)
# Warmup: 75 iterations, single-shot each
# Measurement: 15 iterations, single-shot each
# Timeout: 10 min per iteration
# Threads: 1 thread
# Benchmark mode: Single shot invocation time
# Benchmark: org.renaissance.scala.dotty.JmhDotty.runOperation

# Run progress: 0.00% complete, ETA 00:00:00
# Fork: 1 of 1
# Warmup Iteration   1: dotty-error: error while loading ElementType,
class file /modules/java.base/java/lang/annotation/ElementType.class is broken, reading aborted with class java.lang.RuntimeException
bad constant pool index: 0 at pos: 1220
<failure>

org.renaissance.BenchmarkResult$ValidationException: compilation errors: expected 0 but got 1
	at org.renaissance.BenchmarkResult$Assert.assertEquals(BenchmarkResult.java:167)
	at org.renaissance.scala.dotty.Dotty.$anonfun$run$1(Dotty.scala:228)
	at org.renaissance.jmh.JmhRenaissanceBenchmark.tearDownOperation(JmhRenaissanceBenchmark.java:135)
	at org.renaissance.scala.dotty.jmh_generated.JmhDotty_runOperation_jmhTest.runOperation_SingleShotTime(JmhDotty_runOperation_jmhTest.java:510)
	at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:103)
	at java.base/java.lang.reflect.Method.invoke(Method.java:578)
	at org.openjdk.jmh.runner.BenchmarkHandler$BenchmarkTask.call(BenchmarkHandler.java:475)
	at org.openjdk.jmh.runner.BenchmarkHandler$BenchmarkTask.call(BenchmarkHandler.java:458)
	at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:317)
	at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:572)
	at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:317)
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1144)
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:642)
	at java.base/java.lang.Thread.run(Thread.java:1583)




# Run complete. Total time: 00:00:03

[lbulej]

Thanks for the report, noted. I have no idea what Scala or Dotty is doing either, but apparently they are trying to read class files and encounter something unexpected in the class file content due to the change. In either case, this will require updating Dotty (if this is fixed upstream), which may require more than a simple version bump in the dependencies, so it might take some time. We may need to mark the benchmark as incompatible with JDK21 for the time being (similar to what we'll probably have to do with Spark until version 3.5 is released).

[parttimenerd]

This is related to scala/scala3#17536 and fixed in main, probably shipped in 3.3.1.

[lbulej]

This is related to lampepfl/dotty#17536 and fixed in main, probably shipped in 3.3.1.

Thanks for the heads up, I'll start looking into updating dotty so that when they make the upstream release, we can just bump to that version.

[bulasevich]

Hi,

Yes, the issue was fixed in lampepfl v3.3.1.
scala3-compiler update requires scalaVersion update:

diff --git a/build.sbt b/build.sbt
index 8613a311..81c62b4b 100644
--- a/build.sbt
+++ b/build.sbt
@@ -60,7 +60,7 @@ ThisBuild / Compile / scalacOptions += "-target:jvm-1.8"
 ThisBuild / git.useGitDescribe := true

 val scalaVersion212 = "2.12.15"
-val scalaVersion213 = "2.13.8"
+val scalaVersion213 = "2.13.11"

 val modulesPropertiesName = "modules.properties"
 val benchmarksPropertiesName = "benchmarks.properties"
@@ -346,7 +346,7 @@ lazy val scalaDottyBenchmarks = (project in file("benchmarks/scala-dotty"))
     scalaVersion := scalaVersion213,
     scalacOptions += "-Ytasty-reader",
     libraryDependencies ++= Seq(
-      "org.scala-lang" % "scala3-compiler_3" % "3.0.2",
+      "org.scala-lang" % "scala3-compiler_3" % "3.3.1-RC1",
       // The following is required to compile the workload sources.
       "org.scala-lang" % "scala-compiler" % scalaVersion.value
     ),

However, this simple change introduces another build problem. I would appreciate it if someone would look into this.

[error] renaissance/benchmarks/scala-dotty/src/main/scala/org/renaissance/scala/dotty/Dotty.scala:202:61: Unsupported Scala 3 union in parameter value reporter; found in method process in class dotty.tools.dotc.Driver.
[error]   override def run(bc: BenchmarkContext): BenchmarkResult = {
[error]                                                             ^
[error] one error found
[error] (scalaDottyBenchmarks / Compile / compileIncremental) Compilation failed

[lbulej]

However, this simple change introduces another build problem. I would appreciate it if someone would look into this.

It's a bit of a dependency hell — the Dotty update is among targets for the next release to ensure compatibility with latest JDK.