lrytz

/*
 * Scala (https://www.scala-lang.org)
 *
 * Copyright EPFL and Lightbend, Inc.
 *
 * Licensed under Apache License 2.0
 * (http://www.apache.org/licenses/LICENSE-2.0).
 *
 * See the NOTICE file distributed with this work for
 * additional information regarding copyright ownership.

lrytz

import com.google.monitoring.runtime.instrumentation.AllocationRecorder
import com.google.monitoring.runtime.instrumentation.Sampler

import scala.collection.convert._
import scala.collection.JavaConverters._

// download java-allocation-instrumenter-3.2.0.jar from here:
//   http://repo1.maven.org/maven2/com/google/code/java-allocation-instrumenter/java-allocation-instrumenter/3.2.0/

// compile and run with

lrytz

See https://github.com/scala/scala/releases/tag/v2.12.8

lrytz

package scala.collection.immutable

import scala.collection.{IterableOnce, Iterator}

class LazyListLazinessTest {
  import LazyListLazinessTest._

  def assertEquals(a: Int, b: Int): Unit = ()

  /* op laziness tests */

lrytz

The Scala 2.12/2.13 Inliner and Optimizer

tl;dr.

• Don't inline from your dependencies when publishing a library, it breaks binary compatibility. Use -opt-inline-from:my.package.** to only inline from packages within your library.
• When compiling with the inliner enabled, ensure that the run-time classpath is exactly the same as the compile-time classpath.
• Don't enable the optimizer for development: it breaks sbt's incremental compilation, and it makes the compiler slower. Only enable it for testing, on CI and to build releases.
• The @inline annotation only has an effect if the inliner is enabled. It tells the inliner to always try to inline the annotated method or callsite.
• Without the @inline annotation, the inliner generally inlines higher-order methods and forwarder methods. The main goal is to eliminate megamorphic callsites due to functions passed as argument, and to eliminate value boxing. Other optimizations are delegated to the JVM.

lrytz

jabba use 1.8.191
for sv in 2.13.0-pre-84de40d 2.13.0-pre-84de40d-noopt 2.13.0-pre-8d17277-SNAPSHOT; do
  for vm in 1.8.191 1.8.172-graal-ce-rc7 1.8.172-graal-ee-rc7; do
    echo "----- $sv ----- $vm -----"
    sbt \
      'set resolvers in ThisBuild ++= List("scala-integration" at "https://scala-ci.typesafe.com/artifactory/scala-integration/", "scala-release-temp" at "https://scala-ci.typesafe.com/artifactory/scala-release-temp/", "scala-pr" at "https://scala-ci.typesafe.com/artifactory/scala-pr-validation-snapshots/")' \
      "set scalaVersion in ThisBuild := \"$sv\"" \
      clean \
      "hot -jvm $(jabba which $vm)/bin/java -psource=scalap -f 1 -wi 20 -w 10 -i 10 -r 10"
  done

lrytz

{
    "global": {
        "check_for_updates_on_startup": true,
        "show_in_menu_bar": true,
        "show_profile_name_in_menu_bar": false
    },
    "profiles": [
        {
            "complex_modifications": {
                "parameters": {

lrytz

Here's a javac crash with an incomplete compilation classpath.

$> rm *.class

$> java -version
java version "1.8.0_172"
Java(TM) SE Runtime Environment (build 1.8.0_172-b11)
Java HotSpot(TM) 64-Bit Server VM (build 25.172-b11, mixed mode)

lrytz

object SerDes {
  import java.io._
  def serialize(obj: AnyRef): Array[Byte] = {
    val buffer = new ByteArrayOutputStream
    val out = new ObjectOutputStream(buffer)
    out.writeObject(obj)
    buffer.toByteArray
  }

  def deserialize(a: Array[Byte]): AnyRef = {

lrytz

import java.lang.invoke.SerializedLambda

// lambda syntax for this type uses LambdaMetaFactory
trait SamT1 {
  def foo(x: Int): Int
}

// lambda syntax for this type creates a class at compile-time
trait SamT2 {
  def foo(x: Int): Int