Disable invokedynamic bytecode for legacy Gradle instrumentation

[daniel-mohedano]

What Does This Do

• Disables invokedynamic bytecode generation for the legacy ([3.0, 8.3)) Gradle instrumentation to keep it compatible with Gradle versions older than 7.0.
• Bumps the oldest gradle legacy test from 3.5 to 4.10 so that it is compatible with the project's TestKit and therefore executed (it was currently being skipped).

Motivation

#11436 bumped the project's Gradle version from 8.14.5 to 9.5.1. The Groovy version bundled with Gradle was also bumped, from 3.0 to 4.0. This version of Groovy now enables invokedynamic bytecode generation by default, instead of using the classic call-site caching mechanism used previously.

Parts of the legacy Gradle instrumentation are implemented in Groovy and compiled with the project's bundled Groovy compiler. After the bump, the dynamic calls in the code are emitted as invokedynamic instructions that bootstrap through org.codehaus.groovy.vmplugin.v8.IndyInterface.bootstrap(...), instead of the previous call-site dispatch via org.codehaus.groovy.runtime.callsite.CallSite.

These instrumentation classes are loaded into the user's Gradle daemon at runtime, so they have to link against the Groovy runtime bundled in that daemon's Gradle distribution, which can be much older than the Gradle/Groovy used to build the agent. vmplugin.v8.IndyInterface only exists from Groovy 3.0 onwards (in Groovy 2.x the equivalent class lived under vmplugin.v7). As a result, any build run with a Gradle distribution that bundles Groovy 2.x, Gradle 6.x and earlier (Gradle 7.0 was the first to bundle Groovy 3.0), cannot resolve the bootstrap method. The instrumentation classes fail to link, so CI Visibility never instruments the project's test tasks and no test events are produced.

Additional Notes

The failure was caught through the netflix-zuul and reactive-streams-jvm projects in the test-environment, as the "oldest version" smoke test was being skipped.

Contributor Checklist

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  Use solves instead, and assign the PR milestone to the issue
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  • Remove your PR from the merge queue with /merge -c
  • Skip all merge queue checks with /merge -f --reason "reason"; please use this judiciously, as some checks do not run at the PR-level (note: the PR still needs to be mergeable, this will only skip the pre-merge build)
  • Get more information in this doc

Jira ticket: [PROJ-IDENT]

[cit-pr-commenter-54b7da]

Test Environment - sbt-scalatest

Job Status: success

Scenario	Overhead (%)
agent	53.18
agentEvpProxy	53.50

[cit-pr-commenter-54b7da]

Test Environment - netflix-zuul

Job Status: success

Scenario	Overhead (%)
agent	86.92
agentless	80.29
agentlessCodeCoverage	95.81
agentlessLineCoverage	111.95

[cit-pr-commenter-54b7da]

Test Environment - nebula-release-plugin

Job Status: success

Scenario	Overhead (%)
agent	35.41
agentless	34.77
agentlessCodeCoverage	43.70
agentlessLineCoverage	75.34

[cit-pr-commenter-54b7da]

Test Environment - reactive-streams-jvm

Job Status: success

Scenario	Overhead (%)
agent	23.13
agentless	18.65
agentlessCodeCoverage	20.06
agentlessLineCoverage	30.04

[cit-pr-commenter-54b7da]

Test Environment - pass4s

Job Status: success

Scenario	Overhead (%)
agent	12.79
agentless	11.45
agentlessCodeCoverage	17.84

[dd-octo-sts]

🟡 Java Benchmark SLOs — Performance SLO warning (near threshold)

Suite	Status
Startup	🟡 warning

SLO thresholds are defined here based on automatically generated metrics. A warning is raised when results are within 5% of the threshold.

PR vs. master results

Scenario	Candidate	master	Δ (95% CI of mean)
startup:insecure-bank:iast:Agent	14.86 s	14.69 s	[+0.3%; +2.1%] (maybe worse)
startup:insecure-bank:tracing:Agent	13.70 s	13.69 s	[-0.7%; +0.8%] (no difference)
startup:petclinic:appsec:Agent	17.44 s	17.21 s	[+0.4%; +2.4%] (maybe worse)
startup:petclinic:iast:Agent	17.44 s	17.48 s	[-1.2%; +0.7%] (no difference)
startup:petclinic:profiling:Agent	17.46 s	16.96 s	[-1.6%; +7.5%] (no difference)
startup:petclinic:sca:Agent	17.54 s	17.42 s	[-0.1%; +1.5%] (no difference)
startup:petclinic:tracing:Agent	16.07 s	16.53 s	[-7.0%; +1.5%] (no difference)

Commit: a21f3068 · CI Pipeline · Benchmarking Platform UI

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Load and DaCapo benchmarks can be triggered manually in the GitLab pipeline. Results will appear in the Benchmarking Platform UI after completion.

[cit-pr-commenter-54b7da]

Test Environment - jolokia

Job Status: success

Scenario	Overhead (%)
agent	95.07
agentless	89.29
agentlessCodeCoverage	99.65
agentlessLineCoverage	99.86

[bric3]

praise: TIL

[cit-pr-commenter-54b7da]

Test Environment - sonar-java

Job Status: success

Scenario	Overhead (%)
agent	15.96
agentless	-1.73
agentlessCodeCoverage	41.16
agentlessLineCoverage	115.16

[daniel-mohedano]

/merge

[gh-worker-devflow-routing-ef8351]

View all feedbacks in Devflow UI.

2026-06-10 16:55:13 UTC ℹ️ Start processing command /merge

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2026-06-10 16:55:18 UTC ℹ️ MergeQueue: pull request added to the queue

The expected merge time in master is approximately 1h (p90).

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2026-06-10 17:57:03 UTC ℹ️ MergeQueue: This merge request was merged