Kotlin: support 2.4.20 by andersfugmann · Pull Request #22404 · github/codeql

andersfugmann · 2026-08-21T11:44:17Z

Summary

Add support for Kotlin 2.4.20 in the Kotlin extractor.

The release removes the remaining ComponentRegistrar API and requires an explicit opt-in for deprecated K1 compiler APIs. It also changes compiler-generated IR used by interface forwarders and repeatable annotations. The extractor adapts to these changes while preserving compatibility with Kotlin 1.8.0 and later supported versions.

Changes

Change	Motivation
Add standalone, embeddable, and standard-library 2.4.20 artefacts	Build and run the extractor against the published Kotlin 2.4.20 compiler.
Add a 2.4.20-specific `CompilerPluginRegistrar` implementation	`ComponentRegistrar` is absent from Kotlin 2.4.20, as described in https://youtrack.jetbrains.com/issue/KT-85816.
Package the legacy `ComponentRegistrar` service only before 2.4.20	Older compilers still require the service, while Kotlin 2.4.20 cannot load its removed API.
Opt in to `org.jetbrains.kotlin.K1Deprecation` from 2.4.20	The extractor still uses K1 compatibility APIs. Kotlin 2.4.20 requires the opt-in described in https://youtrack.jetbrains.com/issue/KT-86046.
Reuse the `annotationClass` compatibility extension	Kotlin 2.4.20 rejects the previous IR parent access. The compatibility extension also compiles with Kotlin 1.8.0.
Assign generated interface forwarders the enclosing class location	Kotlin 2.4.20 reports synthetic offsets for these declarations. Using the enclosing class preserves their previous observable location.
Make 2.4.20 the development and Kotlin 2 test default	Exercise the latest supported compiler in normal development and tests.
Update the support documentation and change note	Document Kotlin 2.4.20 as fully supported.

Compatibility

Compiler variants before 2.4.20 retain their existing registrar and service packaging.
The K1 opt-in changes compilation only.
Repeatable annotation extraction uses the existing cross-version compatibility path.
Generated interface forwarders retain their previous observable locations.

Validation

Built the standalone and embeddable Kotlin 2.4.20 extractor variants with JDK 17.
Built the full Java CodeQL distribution with all Kotlin extractor variants.
Ran the interface-forwarder, repeatable-annotation, and future-version diagnostic integration tests sequentially against kotlinc 2.4.20.
All 3 integration tests and their 4 nested QL tests passed.

No tests are disabled. The only changed generated expectation is the future-version diagnostic.

andersfugmann · 2026-08-28T11:41:57Z

Bumped artifacts to Kotlin 2.4.20-RC2

Copilot

Copilot review overview

Review tier: Balanced
Findings: None

What changed in this PR

Adds preliminary Kotlin 2.4.20-RC2 extractor support while continuing to reject Kotlin 2.4.20 GA.

Changes:

Adds RC2 compiler dependencies and extractor variants.
Adapts compiler registration, annotations, and synthetic forwarder locations.
Updates defaults, diagnostics, documentation, and release notes.

File	Description
`MODULE.bazel`	Registers RC2 dependency repositories.
`java/ql/lib/change-notes/2026-08-21-kotlin-2.4.20.md`	Announces preliminary support.
`java/ql/integration-tests/kotlin/all-platforms/diagnostics/kotlin-version-too-new/fake-kotlinc-source/kotlin/KotlinVersion.java`	Tests the GA rejection boundary.
`java/ql/integration-tests/kotlin/all-platforms/diagnostics/kotlin-version-too-new/diagnostics.expected`	Updates the expected diagnostic.
`java/kotlin-extractor/versions.bzl`	Adds the RC2 extractor version.
`java/kotlin-extractor/src/main/kotlin/utils/versions/v_2_4_20-RC2/Kotlin2ComponentRegistrar.kt`	Implements the supported registrar API.
`java/kotlin-extractor/src/main/kotlin/MetaAnnotationSupport.kt`	Uses compatible annotation-class access.
`java/kotlin-extractor/src/main/kotlin/KotlinFileExtractor.kt`	Stabilizes generated forwarder locations.
`java/kotlin-extractor/dev/wrapper.py`	Makes RC2 the development default.
`java/kotlin-extractor/deps/kotlin-stdlib-2.4.20-RC2.jar`	Adds the RC2 standard library artifact.
`java/kotlin-extractor/deps/kotlin-compiler-embeddable-2.4.20-RC2.jar`	Adds the embeddable compiler artifact.
`java/kotlin-extractor/deps/kotlin-compiler-2.4.20-RC2.jar`	Adds the standalone compiler artifact.
`java/kotlin-extractor/BUILD.bazel`	Configures version-specific APIs and services.
`docs/codeql/reusables/supported-versions-compilers.rst`	Documents preliminary RC2 support.

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jketema

First round of comments. There is an RC3 btw.

andersfugmann · 2026-09-03T12:07:40Z

First round of comments. There is an RC3 btw.

I will address the other comments first and then push an update to move support to RC3.

jketema

One remaining question, otherwise this LGTM.

jketema · 2026-09-03T14:53:21Z

            metaAnnotations.find {
-                it.symbol.owner.parentAsClass.fqNameWhenAvailable ==
-                    JvmAnnotationNames.REPEATABLE_ANNOTATION
+                it.annotationClass.fqNameWhenAvailable == JvmAnnotationNames.REPEATABLE_ANNOTATION


Why does this work with earlier Kotlin versions?

annotationClass resolves the class though symbol.owner.constructedClass, which is available for all Kotlin versions, and is already (prior to this PR) used in groupRepeatableAnnotations.

symbol.owner.constructedClass and parentAsClass are for an IrConstructor semantically equivalent. constructor.constructedClass is implemented as constructor.parent as IrClass. parentAsClass also reads parent and requires it to be an IrClass. The only difference is the exception produces if its not an IrClass

Copilot has scanned all the supported versions (>= 1.8.0) to verify that its supported:

I checked every compiler variant supported by this extractor, from Kotlin 1.8.0 through 2.4.20-RC3. constructedClass has the same implementation in all of them. This is safe for our supported versions because an IrConstructor is expected to be parented by the class it constructs

jketema

Approving the current version. I assume this will still need to be rebase/updated a few times, but let's hope the extractor fixes will be stable.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Kotlin 2.4.20-RC removes the remaining ComponentRegistrar API under KT-85816. Use an RC-specific registrar that only implements CompilerPluginRegistrar, and package the legacy ComponentRegistrar service only for older compilers. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Kotlin 2.4.20-RC marks public K1 APIs with K1Deprecation under KT-86046 and rejects the previous repeatable-annotation IR access path. Opt in to K1Deprecation for 2.4.20 and later, and use the existing annotationClass compatibility extension. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Kotlin 2.4.20-RC assigns synthetic source offsets to generated interface forwarders. Use the enclosing class location for each fabricated forwarder and its generated body and accesses, preserving existing database and query output. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Replace the previous 2.4.20-RC dependency set and compatibility marker with RC2 while preserving existing extraction output. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Der 2.4.20-Versuch (e5cd592) brach den CodeQL-Workflow: Der Kotlin- Extractor meldet "Kotlin version 2.4.20 is too recent" (nur RC2 ist supported, GA bewusst blockiert — Tracking github/codeql#22404). Revert auf 2.4.10 (letzte CodeQL-kompatible Version). RELEASE.md- Sektion auf 🚧 Blockiert mit Blocker-Doku umgeschrieben, PARITY-Eintrag korrigiert. Alert #63 bleibt dismissed bis codeql#22404 gemerged ist. 🤖 Generated with Codebuff Co-Authored-By: Codebuff <noreply@codebuff.com>

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

…odeQL Kotlin guard - BotCommandsCatalog (feature-chat) drives HELP_TEXT and the in-app help screen; BotCommandsCatalogTest proves every primary+alias resolves in dispatch(), HelpScreen Robolectric test enforces per-command descriptions (new help_cmd_* strings for !fix/!filter/!boost/!battery/!lut/!colorspace/ !poll/!vote/!pollend/!prev/!play in DE/EN/FR) - sync_wiki.sh now generates Home + User-Guide-EN + User-Guide-FR mirrors with per-language links; offline self-test (6 cases) wired into pre-push gate and CI - new weekly automation-codeql-kotlin.yml watches github/codeql#22404 and comments on issue #110 once Kotlin 2.4.20 GA support lands (exit-code contract, offline fixture self-test) - regenerate fdroidserver-requirements.txt closure (pre-existing drift)

github-actions Bot added documentation Java Kotlin labels Aug 21, 2026

andersfugmann force-pushed the andersfugmann/kotlin-2.4.20rc branch 8 times, most recently from 2fa6f32 to b9c81d5 Compare August 26, 2026 11:25

andersfugmann removed the Java label Aug 26, 2026

andersfugmann self-assigned this Aug 26, 2026

github-actions Bot added the Java label Aug 26, 2026

andersfugmann changed the title ~~Kotlin: support 2.4.20-RC~~ Kotlin: support 2.4.20-RC2 Aug 28, 2026

andersfugmann marked this pull request as ready for review August 28, 2026 11:42

Copilot AI balanced review requested due to automatic review settings August 28, 2026 11:42

andersfugmann requested review from a team as code owners August 28, 2026 11:42

Copilot started reviewing on behalf of andersfugmann August 28, 2026 11:43 View session

Copilot AI reviewed Aug 28, 2026

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andersfugmann mentioned this pull request Aug 28, 2026

Kotlin: cover 2.4.20 language features #22462

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jketema reviewed Sep 2, 2026

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andersfugmann force-pushed the andersfugmann/kotlin-2.4.20rc branch from a07ec7b to 00bb879 Compare September 3, 2026 14:41

andersfugmann changed the title ~~Kotlin: support 2.4.20-RC2~~ Kotlin: support 2.4.20-RC3 Sep 3, 2026

jketema reviewed Sep 3, 2026

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andersfugmann force-pushed the andersfugmann/kotlin-2.4.20rc branch from 00bb879 to e7e97c4 Compare September 4, 2026 08:24

jketema previously approved these changes Sep 4, 2026

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andersfugmann force-pushed the andersfugmann/kotlin-2.4.20rc branch from e7e97c4 to a123d89 Compare September 7, 2026 06:58

andersfugmann and others added 11 commits September 7, 2026 13:26

Kotlin: add 2.4.20-RC artifacts

796790d

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Kotlin: enable 2.4.20-RC support

0e0b862

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Kotlin: make 2.4.20-RC the test default

a5a1878

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Kotlin: document preliminary 2.4.20-RC support

352483f

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Kotlin: support 2.4.20-RC2

b1c4fe7

Replace the previous 2.4.20-RC dependency set and compatibility marker with RC2 while preserving existing extraction output. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Kotlin: document preliminary 2.4.20 support

8301109

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Kotlin: restore future-version diagnostic test

570eba1

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Kotlin: support 2.4.20-RC3

8b72dd3

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

andersfugmann force-pushed the andersfugmann/kotlin-2.4.20rc branch from a123d89 to 8b72dd3 Compare September 7, 2026 11:27

thoser666 mentioned this pull request Sep 7, 2026

Kotlin-Update auf 2.4.20 (stabil) — Alert #63 schließen thoser666/Vivid#110

Open

4 tasks

Kotlin: use 2.4.20 GA

47cc7d8

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

andersfugmann dismissed jketema’s stale review via 47cc7d8 September 7, 2026 13:42

andersfugmann changed the title ~~Kotlin: support 2.4.20-RC3~~ Kotlin: support 2.4.20 Sep 7, 2026

hfhbd mentioned this pull request Sep 7, 2026

Kotlin 2.4.20 is about to be released - please prepare to be ready asap #22381

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Kotlin: support 2.4.20 - #22404

Kotlin: support 2.4.20#22404
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andersfugmann commented Aug 21, 2026 •

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andersfugmann commented Sep 3, 2026 •

edited by jketema

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Summary

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andersfugmann commented Aug 21, 2026 •

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