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Scala 2 team issues. Not for user-facing bugs or directly actionable user-facing improvements. For build/test/infra and for longer-term planning and idea tracking. Our bug tracker is at https://github...
@retronym proposed an idea to improve support for cyclic errors. https://github.com/scala/scala/pull/5724 introduced a stack of completing symbols that are used to report on the culprit of the stub error. However,...
I run the compiler with a flight recorder dump: ``` scalac -J-XX:+UnlockCommercialFeatures -J-XX:+FlightRecorder -J-XX:StartFlightRecording=dumponexit=true,settings=profile,filename=out.jfr ``` Opening the file in JMC, in the Events-Log tab, there's 483 events like this one....
Running `scalac -version` in 2.12.0-SNAPSHOT takes 0.9s, a significant regression from 2.11.8, which took 0.2s. ``` % time scalac -debug -version /Library/Java/JavaVirtualMachines/jbsdk8u112b403_osx_x64/Contents/Home/bin/java -Xmx256M -Xms32M -Xbootclasspath/a:/Users/jason/scala/2.11.8/lib/akka-actor_2.11-2.3.10.jar:/Users/jason/scala/2.11.8/lib/config-1.2.1.jar:/Users/jason/scala/2.11.8/lib/jline-2.12.1.jar:/Users/jason/scala/2.11.8/lib/scala-actors-2.11.0.jar:/Users/jason/scala/2.11.8/lib/scala-actors-migration_2.11-1.1.0.jar:/Users/jason/scala/2.11.8/lib/scala-compiler.jar:/Users/jason/scala/2.11.8/lib/scala-continuations-library_2.11-1.0.2.jar:/Users/jason/scala/2.11.8/lib/scala-continuations-plugin_2.11.8-1.0.2.jar:/Users/jason/scala/2.11.8/lib/scala-library.jar:/Users/jason/scala/2.11.8/lib/scala-parser-combinators_2.11-1.0.4.jar:/Users/jason/scala/2.11.8/lib/scala-reflect.jar:/Users/jason/scala/2.11.8/lib/scala-swing_2.11-1.0.2.jar:/Users/jason/scala/2.11.8/lib/scala-xml_2.11-1.0.4.jar:/Users/jason/scala/2.11.8/lib/scalap-2.11.8.jar -classpath "" -Dscala.home=/Users/jason/scala/2.11.8 -Dscala.usejavacp=true -Denv.emacs=...
A follow-up for https://github.com/scala/scala/pull/5298 / https://github.com/scala/scala-dev/issues/121 Maybe one day we can remove the hand-specialized `JFunctionN$sp..` classes by adjusting specialization to leave the specialized method abstract, instead of the generic one....
@retronym says: > See code around `tupleClassConstructors` for the spot in the backend that could be extended to know about `Lazy*` to optimize the case of non-capturing local lazies to...
When enabling the sbt build for running the tests on jenkins, we found that the JVM instance to run partest (and thus the compiler instances) needs more memory than on...
`looksLikeForwarderOrFactoryOrTrivial` identifies forwarders, factories and trivial methods. Currently that method doesn't know a field read or a method call targets a public or private field or method. It approximates this...
The use of ASM Analyzers in the inliner/optimizer is very allocation heavy. This can be observed easily with a profiler, there is basically constant minor GC going on as soon...
We've been talking a few times already about running the optimizer separately from compilation, let's collect the thoughts here. This obviously overlaps with @DarkDimius' work on the dotty linker, and...
``` scala> abstract class Inline5 extends (AnyRef => AnyRef) { def apply(a: AnyRef) = a; def test(ls: List[AnyRef]) = ls.mapConserve(this) } defined class Inline5 scala> :javap -c Inline5#test public scala.collection.immutable.List...