8330027: Identity hashes of archived objects must be based on a reproducible random seed

[tstuefe]

This fixes an issue with CDS archive reproducibility that can happen under rare circumstances. See original JBS issue for details.

I had to manually resolve the hunk in src/hotspot/share/cds/heapShared.cpp because both

• 8251330: Reorder CDS archived heap to speed up relocation
• 8329431: Improve speed of writing CDS heap objects
  were missing.

Resolve was trivial.

---

Progress

• Change must be properly reviewed (1 review required, with at least 1 Reviewer)
• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• JDK-8330027 needs maintainer approval

Issue

• JDK-8330027: Identity hashes of archived objects must be based on a reproducible random seed (Bug - P4 - Approved)

Reviewers

• Paul Hohensee (@phohensee - Reviewer)

Reviewing

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Update a local copy of the PR:
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$ git pr checkout 194

View PR using the GUI difftool:
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[bridgekeeper]

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[openjdk]

@tstuefe This change now passes all automated pre-integration checks.

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After integration, the commit message for the final commit will be:

8330027: Identity hashes of archived objects must be based on a reproducible random seed

Reviewed-by: phh

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At the time when this comment was updated there had been 1 new commit pushed to the master branch:

• 7629aa6: 8322726: C2: Unloaded signature class kills argument value

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[openjdk]

This backport pull request has now been updated with issue from the original commit.

[mlbridge]

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[openjdk]

⚠️ @tstuefe This change is now ready for you to apply for maintainer approval. This can be done directly in each associated issue or by using the /approval command.

[tstuefe]

/approval request This fixes an issue with CDS archive reproducibility that can happen under rare circumstances. Since CDS reproducibility issues are time consuming to debug and the fix is simple and low risk, I would like to see this issue fixed in JDK 22.

[openjdk]

@tstuefe
8330027: The approval request has been created successfully.

[tstuefe]

Got approval.

/integrate

[openjdk]

Going to push as commit 9b3187f.
Since your change was applied there have been 4 commits pushed to the master branch:

• 9486b7c: 8324243: Compilation failures in java.desktop module with gcc 14
• 2ec7dbf: 8331352: error: template-id not allowed for constructor/destructor in C++20
• ccef462: 8328997: Remove unnecessary template parameter lists in GrowableArray
• 7629aa6: 8322726: C2: Unloaded signature class kills argument value

Your commit was automatically rebased without conflicts.

[openjdk]

@tstuefe Pushed as commit 9b3187f.

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