8323552: AbstractMemorySegmentImpl#mismatch returns -1 when comparing distinct areas of the same instance of MemorySegment

[minborg]

Hi all,

This pull request contains a backport of commit 93579c29 from the openjdk/jdk repository.

The commit being backported was authored by Per Minborg on 25 Mar 2024 and was reviewed by Maurizio Cimadamore.

Thanks!

---

Progress

• Change must be properly reviewed (1 review required, with at least 1 Reviewer)
• JDK-8323552 needs maintainer approval
• Change must not contain extraneous whitespace
• Commit message must refer to an issue

Issue

• JDK-8323552: AbstractMemorySegmentImpl#mismatch returns -1 when comparing distinct areas of the same instance of MemorySegment (Bug - P4 - Approved)

Reviewers

• Martin Doerr (@TheRealMDoerr - Reviewer)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk21u-dev.git pull/404/head:pull/404
$ git checkout pull/404

Update a local copy of the PR:
$ git checkout pull/404
$ git pull https://git.openjdk.org/jdk21u-dev.git pull/404/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 404

View PR using the GUI difftool:
$ git pr show -t 404

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk21u-dev/pull/404.diff

Webrev

Link to Webrev Comment

[bridgekeeper]

👋 Welcome back pminborg! 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.

[openjdk]

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

ℹ️ This project also has non-automated pre-integration requirements. Please see the file CONTRIBUTING.md for details.

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

8323552: AbstractMemorySegmentImpl#mismatch returns -1 when comparing distinct areas of the same instance of MemorySegment

Reviewed-by: mdoerr

You can use pull request commands such as /summary, /contributor and /issue to adjust it as needed.

At the time when this comment was updated there had been 224 new commits pushed to the master branch:

• 0dcbc1d: 8324668: JDWP process management needs more efficient file descriptor handling
• 42e6a97: 8323670: A few client tests intermittently throw ConcurrentModificationException
• 55e97ce: 8319773: Avoid inflating monitors when installing hash codes for LM_LIGHTWEIGHT
• b56f0c0: 8326106: Write and clear stack trace table outside of safepoint
• 8d4f686: 8312229: Crash involving yield, switch and anonymous classes
• 2a21044: 8331573: Rename CollectedHeap::is_gc_active to be explicitly about STW GCs
• 362ecac: 8331164: createJMHBundle.sh download jars fail when url needed to be redirected
• dc8b95f: 8328075: Shenandoah: Avoid forwarding when objects don't move in full-GC
• 9971c63: 8307788: vmTestbase/gc/gctests/LargeObjects/large003/TestDescription.java timed out
• 97c01b1: 8317288: [macos] java/awt/Window/Grab/GrabTest.java: Press on the outside area didn't cause ungrab
• ... and 214 more: https://git.openjdk.org/jdk21u-dev/compare/3050bf3bd034b6b68a9c8fe09060c4e0a5472785...master

As there are no conflicts, your changes will automatically be rebased on top of these commits when integrating. If you prefer to avoid this automatic rebasing, please check the documentation for the /integrate command for further details.

As you do not have Committer status in this project an existing Committer must agree to sponsor your change. Possible candidates are the reviewers of this PR (@TheRealMDoerr) but any other Committer may sponsor as well.

➡️ To flag this PR as ready for integration with the above commit message, type /integrate in a new comment. (Afterwards, your sponsor types /sponsor in a new comment to perform the integration).

[openjdk]

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

[mlbridge]

Webrevs

• 00: Full (3ef0f630)

[shipilev]

Hey @minborg! Please enable GHA for your jdk21u-dev fork and trigger it :)

[shipilev]

Hey @minborg :) Are you planning to complete this one, or need someone else to take over?

[TheRealMDoerr]

Ok, this is basically a clean backport + Copyright header fix.

[openjdk]

⚠️ @minborg 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.

[minborg]

/approval request This is a clean backport of a bug discovered in 22

[openjdk]

@minborg
8323552: The approval request has been created successfully.

[TheRealMDoerr]

This one is ready for integration.

[minborg]

This one is ready for integration.

It appears JDK-8323552 is not approved by the maintainer.

[shipilev]

It appears JDK-8323552 is not approved by the maintainer.

Looks like Christoph wanted 22u backport first. Feel free to re-request the approval. Probably just put jdk21u-fix-request label back?

[TheRealMDoerr]

Right, the approval has been revoked. I have rerequested it by adding the label.

[shipilev]

Now you should be fine to integrate, @minborg!

[minborg]

/integrate

[openjdk]

@minborg
Your change (at version 3ef0f63) is now ready to be sponsored by a Committer.

[TheRealMDoerr]

/sponsor

[openjdk]

Going to push as commit 0d9833e.
Since your change was applied there have been 224 commits pushed to the master branch:

• 0dcbc1d: 8324668: JDWP process management needs more efficient file descriptor handling
• 42e6a97: 8323670: A few client tests intermittently throw ConcurrentModificationException
• 55e97ce: 8319773: Avoid inflating monitors when installing hash codes for LM_LIGHTWEIGHT
• b56f0c0: 8326106: Write and clear stack trace table outside of safepoint
• 8d4f686: 8312229: Crash involving yield, switch and anonymous classes
• 2a21044: 8331573: Rename CollectedHeap::is_gc_active to be explicitly about STW GCs
• 362ecac: 8331164: createJMHBundle.sh download jars fail when url needed to be redirected
• dc8b95f: 8328075: Shenandoah: Avoid forwarding when objects don't move in full-GC
• 9971c63: 8307788: vmTestbase/gc/gctests/LargeObjects/large003/TestDescription.java timed out
• 97c01b1: 8317288: [macos] java/awt/Window/Grab/GrabTest.java: Press on the outside area didn't cause ungrab
• ... and 214 more: https://git.openjdk.org/jdk21u-dev/compare/3050bf3bd034b6b68a9c8fe09060c4e0a5472785...master

Your commit was automatically rebased without conflicts.

[openjdk]

@TheRealMDoerr @minborg Pushed as commit 0d9833e.

💡 You may see a message that your pull request was closed with unmerged commits. This can be safely ignored.