JDK 25 compatibility: Drop JDK 8 support, JCTools 4.x, VarHandle fencing, CI modernization#6
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halotukozak wants to merge 19 commits intobump-dependenciesfrom
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JDK 25 compatibility: Drop JDK 8 support, JCTools 4.x, VarHandle fencing, CI modernization#6halotukozak wants to merge 19 commits intobump-dependenciesfrom
halotukozak wants to merge 19 commits intobump-dependenciesfrom
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Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
- Change jcTools_Version from "3.3.0" to "4.0.5" in build.sbt - JCTools 4.x replaces sun.misc.Unsafe with VarHandle (JDK 25-safe) - Cross-compilation verified on Scala 2.12.20, 2.13.16, 3.3.5 - Shaded monix-internal-jctools assembly rebuilt with no sun/misc references
- JCTools upgraded 3.3.0 -> 4.0.5 (VarHandle-based, JDK 25-safe) - Full JVM test suite: 20,885 tests pass, 0 failures across Scala 2.12/2.13/3.3 - Updated ROADMAP.md: Phase 4 plan 01 marked complete, in-progress status Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
…ions - Replace olafurpg/setup-scala@v10 with actions/setup-java@v4 (temurin) in all jobs - Add JDK 21 and 25 to jvm-tests matrix (was [8, 11], now [8, 11, 21, 25]) - Update actions/checkout@v2 -> @v4, actions/cache@v1 -> @v4, actions/setup-node@v2.1.2 -> @v4 - Update all runs-on from ubuntu-20.04 to ubuntu-latest (20.04 is EOL) - JS tests, MiMa, unidoc, publish jobs stay on JDK 8 (matrix unchanged)
- Update ROADMAP.md: phase 04 progress updated (2/2 plans complete)
Already in .gitignore, these files were tracked from before the ignore rule. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
…nce() in queue wrappers - Remove direct sun.misc.Unsafe import from FromMessagePassingQueue.scala - Remove direct sun.misc.Unsafe import from FromCircularQueue.scala - Add java.lang.invoke.VarHandle import to both files - Replace UNSAFE instance field + fullFence() calls with VarHandle.fullFence() static call - Eliminates JDK 25 JEP 498 Phase 2 runtime warnings from Monix's own Scala queue files - VarHandle.fullFence() (JDK 9+) is safe since Java8* classes are guarded by HAS_JAVA8_INTRINSICS
halotukozak
changed the base branch from
series/3.x-avs
to
bump-dependencies
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Pull request overview
Updates Monix’s build/tooling and CI to improve compatibility with newer JDKs (incl. JDK 25), modernizes GitHub Actions, and bumps key build dependencies (including JCTools).
Changes:
- Bumped build tooling and plugins (SBT 1.10.7, sbt plugins, scalac/tpolecat configuration) and updated JCTools to 4.0.5.
- Replaced
Unsafe.fullFence()usage withVarHandle.fullFence()in two JVM queue adapters. - Modernized CI workflows (actions v4,
ubuntu-latest, expanded JVM test matrix to JDK 8/11/21/25).
Reviewed changes
Copilot reviewed 3 out of 4 changed files in this pull request and generated 2 comments.
Show a summary per file
| File | Description |
|---|---|
| project/plugins.sbt | Updates sbt plugin versions; adds a dependency scheme override for geny. |
| project/build.properties | Bumps sbt version to 1.10.7. |
| monix-execution/shared/src/main/scala/monix/execution/CancelablePromise.scala | Suppresses an exhaustivity warning for a list destructure. |
| monix-execution/jvm/src/main/scala/monix/execution/internal/collection/queues/FromMessagePassingQueue.scala | Switches fencing implementation to VarHandle.fullFence(). |
| monix-execution/jvm/src/main/scala/monix/execution/internal/collection/queues/FromCircularQueue.scala | Switches fencing implementation to VarHandle.fullFence(). |
| build.sbt | Bumps versions (JCTools, plugins) and adjusts scalac/tpolecat options. |
| .jvmopts | Removes a deprecated JVM option (CMSClassUnloadingEnabled). |
| .gitignore | Ignores .planning/. |
| .github/workflows/build.yml | Modernizes actions/runners; expands JVM matrix and updates Scala versions. |
Comments suppressed due to low confidence (1)
.github/workflows/build.yml:104
- Node.js 14 is end-of-life and may eventually stop being available on GitHub-hosted runners / receive security updates. Since this workflow is being modernized, consider bumping
node-versionto a supported LTS (e.g. 18 or 20) unless Scala.js tooling here explicitly requires 14.
- name: Setup NodeJS
uses: actions/setup-node@v4
with:
node-version: 14
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.../jvm/src/main/scala/monix/execution/internal/collection/queues/FromMessagePassingQueue.scala
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olafurpg/setup-scala installed both Java and SBT. The replacement actions/setup-java@v4 only installs Java. Adding `cache: sbt` both installs SBT and caches ~/.sbt, ~/.ivy2, and ~/.cache/coursier. Also removes redundant manual cache steps — setup-java handles this. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
halotukozak
changed the base branch from
bump-dependencies
to
series/3.x-avs
Remove branch filter from pull_request trigger so CI runs regardless of target branch. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
halotukozak
changed the base branch from
series/3.x-avs
to
bump-dependencies
setup-java's `cache: sbt` only caches directories, it doesn't install sbt. The old olafurpg/setup-scala bundled sbt installation. Use the official sbt/setup-sbt@v1 action to install the sbt launcher. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
…tibility Updated thread naming to use `Thread.threadId` instead of deprecated `Thread.getId` across thread factory implementations.
…ed compatibility" This reverts commit 0fca646.
… implementations
halotukozak
changed the title
…threadId` usage - Refactored thread naming logic to use `ThreadCompatOps` for backward compatibility with JDK < 19. - Removed deprecated `@nowarn` annotations from thread factory implementations.
… JDK compatibility
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Summary
sun.misc.Unsafe.fullFence()calls withVarHandle.fullFence()(JDK 9+) inFromMessagePassingQueue.scalaandFromCircularQueue.scalaolafurpg/setup-scala@v10withactions/setup-java@v4(Temurin), updated all actions to v4, runners toubuntu-latest, added JDK 21 and 25 tojvm-testsmatrixAlso includes infrastructure updates from
bump-dependencies: SBT 1.10.7, Scala 2.12.20/2.13.16/3.3.5, sbt-tpolecat 0.5.3, plugin updates.Test plan
jvm-testsmatrix passes for all 12 combinations (JDK [8, 11, 21, 25] × Scala [2.12, 2.13, 3.3])sun.misc.Unsafewarnings are non-fatalNote: The 40+ Java atomic files and shaded JCTools JAR still use
sun.misc.Unsafefor CAS operations. On JDK 25 (JEP 498 Phase 2), these produce non-fatal warnings. On JDK 26+ (Phase 3), they will need migration toVarHandle— tracked as future work.🤖 Generated with Claude Code