8333884: MemorySegment::reinterpret removes read-only property

[minborg]

This PR proposes to retain the read-only state when any of the MemorySegment::reinterpret methods is called.

Previously, the read-only state was lost and the returned MemorySegment was always writable regardless of the original segment's read-only state.

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Progress

• Change must be properly reviewed (1 review required, with at least 1 Reviewer)
• Change requires CSR request JDK-8333892 to be approved
• Change must not contain extraneous whitespace
• Commit message must refer to an issue

Issues

• JDK-8333884: MemorySegment::reinterpret removes read-only property (Bug - P3)(⚠️ The fixVersion in this issue is [23, 24] but the fixVersion in .jcheck/conf is 24, a new backport will be created when this pr is integrated.)
• JDK-8333892: MemorySegment::reinterpret removes read-only property (CSR)

Reviewers

• Maurizio Cimadamore (@mcimadamore - Reviewer) 🔄 Re-review required (review applies to 538eb2ed)
• Jorn Vernee (@JornVernee - Reviewer)

Reviewing

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$ git checkout pull/19629

Update a local copy of the PR:
$ git checkout pull/19629
$ git pull https://git.openjdk.org/jdk.git pull/19629/head

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Webrev

Link to Webrev Comment

[minborg]

/csr

[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:

8333884: MemorySegment::reinterpret removes read-only property

Reviewed-by: jvernee, mcimadamore

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 1 new commit pushed to the master branch:

• ff49f67: 8335775: Remove extraneous 's' in comment of rawmonitor.cpp test file

Please see this link for an up-to-date comparison between the source branch of this pull request and the master branch.
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➡️ To integrate this PR with the above commit message to the master branch, type /integrate in a new comment.

[openjdk]

@minborg has indicated that a compatibility and specification (CSR) request is needed for this pull request.

@minborg please create a CSR request for issue JDK-8333884 with the correct fix version. This pull request cannot be integrated until the CSR request is approved.

[openjdk]

@minborg The following label will be automatically applied to this pull request:

• core-libs

When this pull request is ready to be reviewed, an "RFR" email will be sent to the corresponding mailing list. If you would like to change these labels, use the /label pull request command.

[mlbridge]

Webrevs

• 03: Full (5c21a5ff)
• 02: Full - Incremental (bc0ade8a)
• 01: Full - Incremental (538eb2ed)
• 00: Full (acebad9b)

[mcimadamore]

Note that asSlice methods also lacks a similar guarantee on read-only (but the impl works fine there)

[minborg]

Note that asSlice methods also lacks a similar guarantee on read-only (but the impl works fine there)

Even though not mentioned in the original issue, we could add documentation for this here as well. Or maybe via https://bugs.openjdk.org/browse/JDK-8333886 ?

[mcimadamore]

Note that asSlice methods also lacks a similar guarantee on read-only (but the impl works fine there)

Even though not mentioned in the original issue, we could add documentation for this here as well. Or maybe via https://bugs.openjdk.org/browse/JDK-8333886 ?

Or a new issue - I'm fine with both approaches. Whatever requires less work. Since you are already adding these "if this segment is read-only... ", maybe it would be simpler to review as part of this PR?

[JornVernee]

Thanks for fixing!

[openjdk]

@minborg this pull request can not be integrated into master due to one or more merge conflicts. To resolve these merge conflicts and update this pull request you can run the following commands in the local repository for your personal fork:

git checkout reinterpret-ro-state
git fetch https://git.openjdk.org/jdk.git master
git merge FETCH_HEAD
# resolve conflicts and follow the instructions given by git merge
git commit -m "Merge master"
git push

[minborg]

/integrate

[openjdk]

Going to push as commit 6f7f0f1.
Since your change was applied there have been 3 commits pushed to the master branch:

• b83766e: 8335632: jdk/jfr/api/consumer/streaming/TestJVMExit.java failed with "Process [...] is no longer alive"
• 7efe160: 8335730: JFR: Clean up jdk.jfr
• ff49f67: 8335775: Remove extraneous 's' in comment of rawmonitor.cpp test file

Your commit was automatically rebased without conflicts.

[openjdk]

@minborg Pushed as commit 6f7f0f1.

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