8365994: ZGC: Incorrect type signature in ZMappedCache comparator

[jsikstro]

Hello,

The comparator with two IntrusiveRBNode* in ZMappedCache has the incorrent type signature. This prevents IntrusiveRBTree from using the comparator as intended during validation, resulting in it using the fallback verify function, which always returns true. This could mask potential issues in the tree structure.

Testing:

• Manually placing an assert in the fallback verify function to see if it is used. It is no longer used with this patch.
• Oracle's tier 1-2

---

Progress

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Issue

• JDK-8365994: ZGC: Incorrect type signature in ZMappedCache comparator (Bug - P4)

Reviewers

• Casper Norrbin (@caspernorrbin - Committer)

Reviewing

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[bridgekeeper]

👋 Welcome back jsikstro! A progress list of the required criteria for merging this PR into master will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

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[openjdk]

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• hotspot-gc

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[caspernorrbin]

Looks good!

[mlbridge]

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• 00: Full (cb42883f)