[#12301] Use stack-passed Set for activeModelReads cycle detection - #12325
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… activeModelReads Replace the shared ConcurrentHashMap.newKeySet() with a Set<Path> passed through the call stack: doReadFileModel() → getEnhancedProperties() → readFileModel(). Each call chain carries its own set, preventing recursive cycles within the same call stack without interfering with parallel threads in PhasingExecutor. This avoids the race condition where a path added by one thread blocks a parallel thread's getEnhancedProperties() from reading that model, while still preventing the StackOverflowError from GH-12301. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
cstamas
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Jun 19, 2026
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@gnodet Please assign appropriate label to PR according to the type of change. |
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Summary
Replace the shared
ConcurrentHashMap.newKeySet()used foractiveModelReadscycle detection with aSet<Path>passed through the call stack.The original fix (PR #12314) used a shared concurrent set across all derived sessions to prevent the StackOverflowError from GH-12301. While this works correctly on
maven-4.0.xtoday, it has a latent race condition: parallel threads inPhasingExecutor(loadFilePom) that read the same model simultaneously can falsely block each other'sgetEnhancedProperties()from reading that model. This race manifests onmaster(brokeConsumerPomBuilderTest.testSimpleConsumerwhen forward-ported as #12317).The fix passes the
Set<Path>as a method parameter through the call chain:doReadFileModel(activeModelReads)→ adds current path, passes to both parent resolution andgetEnhancedProperties()getEnhancedProperties(model, rootDir, activeModelReads)→ checks set before reading root modelreadFileModel(activeModelReads)→ threads the set through the cache callEach call chain (from
readFileModel()entry point) carries its own set, so parallel threads never interfere.Test plan
DefaultModelBuilderTest— 12/12 passConsumerPomBuilderTest— 7/7 passFully automatic review from Claude Code