8359830: Incorrect os.version reported on macOS Tahoe 26 (Beta)

[jaikiran]

Can I please get a review of this change which proposes to address the issue noted in https://bugs.openjdk.org/browse/JDK-8359830?

macOS operating system's newer version 26 (currently in Beta) is reported as a 16 by older versions of XCode. JDK internally uses the NSProcessInfo and NSOperatingSystemVersion APIs to identify the macOS version and set the os.version system property to that value. The current recommended version to build the JDK on macOS is XCode 15.4. The NSOperatingSystemVersion API on that version of XCode reports macOS version as 16 instead of 26.

The commit in this PR updates the JDK code to handle this mismatch and set the os.version appropriately to 26. This fix is similar to what we did with macOS BigSur when the macOS version 10.16 was meant to mean 11 https://bugs.openjdk.org/browse/JDK-8253702.

The existing OsVersionTest has been updated for some trivial clean up. Existing tests in tier1, tier2 and tier3 continue to pass with this change. If anyone has access to a macOS 26 Beta, I request them to build this change and run tier1 tests to help verify that there aren't any failures.

---

Progress

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Issue

• JDK-8359830: Incorrect os.version reported on macOS Tahoe 26 (Beta) (Bug - P3)

Reviewers

• Roger Riggs (@RogerRiggs - Reviewer)
• Kevin Rushforth (@kevinrushforth - Author) Review applies to 6d888de7
• Lance Andersen (@LanceAndersen - Reviewer)

Reviewing

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[bridgekeeper]

👋 Welcome back jpai! 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]

@jaikiran 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:

8359830: Incorrect os.version reported on macOS Tahoe 26 (Beta)

Reviewed-by: rriggs, lancea, kcr

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 14 new commits pushed to the master branch:

• ff24088: 8359919: Minor java.util.concurrent doc improvements
• 5a1301d: 8360548: Parallel: Remove outdated comments in MutableNUMASpace::bias_region
• 5039b42: 8359437: Make users and test suite not able to set LockingMode flag
• ... and 11 more: https://git.openjdk.org/jdk/compare/1fa090524a7c3bb5f2c92fb0f7217b9277ade9d9...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.

➡️ To integrate this PR with the above commit message to the master branch, type /integrate in a new comment.

[openjdk]

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

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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

• 01: Full - Incremental (ae690ae8)
• 00: Full (6d888de7)

[jaikiran]

Existing tests in tier1, tier2 and tier3 continue to pass with this change. If anyone has access to a macOS 26 Beta, I request them to build this change and run tier1 tests to help verify that there aren't any failures.

I got access to a macOS 26 Beta and ran tier1 tests on it with this change. The tests completed fine. Only one CDS test is failing runtime/cds/DeterministicDump.java, but that doesn't look related to this change (I haven't completed analyzed that failure so far):

==============================
Test summary
==============================
   TEST                                         TOTAL  PASS  FAIL ERROR  SKIP   
>> jtreg:test/hotspot/jtreg:tier1                3022  2574     1     0   447 <<
   jtreg:test/jdk:tier1                          2525  2469     0     0    56   
   jtreg:test/langtools:tier1                    4651  4642     0     0     9   
   jtreg:test/jaxp:tier1                            0     0     0     0     0   
   jtreg:test/lib-test:tier1                       37    37     0     0     0   
==============================

[RogerRiggs]

Looks good. Give it a day or so for others to review.

[kevinrushforth]

LGTM

I tested this on macOS 26. Without this patch os.version is set to 16; with this patch, it is correctly set to 26.

I left one possible suggestion, if you want to consider it.

[kevinrushforth]

Since we know Apple jumped from 15 --> 26, would it be more future-proof to change this test to something like this?

    osVer.majorVersion >= 16 && osVer.majorVersion < 26 

This would allow us to work when macOS 27 comes out, in case it reports itself as "17.0" if we don't update the version of Xcode before then.

I can also see the argument for leaving it as you have done. And my guess is that Apple will report macOS 27 as 27 regardless, so this probably doesn't matter.

[jaikiran]

Hello Kevin,

I can also see the argument for leaving it as you have done.

I gave your suggestion some thought. I think it would be simpler (and less confusing) to leave that check in the current form and update it as and when needed depending on whether macOS does report future versions as two different values.

[AlanBateman]

Are there changes for os_bsd.cpp too?

[jaikiran]

Hello Alan,

Are there changes for os_bsd.cpp too?

That's a good catch. I did not know that we have os::get_summary_os_info in that file which too deals with OS name and version. The native functions used in that implementation are sysctl() calls. I experimented on a macOS 26 (Beta) instance and those functions too report the "wrong" version (16) when the JDK is built using XCode 15.4. So this code needs to be addressed too.

This os::get_summary_os_info gets used only through os::print_summary_info (in os.cpp), which gets called for VM crash info reporting as well as java -XX:+UnlockDiagnosticVMOptions -XX:+PrintVMInfoAtExit .... I think we are missing a test for this which might explain why tier1, tier2, tier3 testing of this current change didn't notice that this area too needs a change. I'll update this PR to include this additional code change and introduce a new regression test to catch this issue.

[jaikiran]

I think we are missing a test for this which might explain why tier1, tier2, tier3 testing of this current change didn't notice that this area too needs a change.

It looks like an existing test test/hotspot/jtreg/runtime/ErrorHandling/PrintVMInfoAtExitTest.java might need an update to include a check for the OS version reported in the output.

[jaikiran]

Hello Alan, I've been pursuing this further and there's a way to address this issue in os_bsd.cpp#get_summary_os_info(). The ultimate place where we get the correct version is the plist files that are referenced in this PR. plist files are XML files and to be able to read those semantically, either a XML parser is necessary or we can use the Objective-C APIs that are provided by macOS in the Foundation framework (the same ones that we currently use in the java_props_macosx.c). I've been experimenting with using these Objective-C APIs in this C++ code of hotspot, but have been running into build issues. I am currently discussing those with people familiar with this area and plan to continue pursuing it further. However, in the meantime, if it's OK then I would like to go ahead and integrate the current state of this PR into mainline (and have it backported), so that it gets the necessary testing time both on macOS 26 Beta and other versions. The few places where this misreporting of macOS version in os_bsd.cpp is going to impact is the VM error reporting (in hs_err files for example) and the output of the newly introduced -XX:+PrintJVMInfoAtExit option. So I think we can address this issue separately (I'll create a follow up issue to track that work). Do you think it's OK to go ahead with this integration?

[jaikiran]

I've been experimenting with using these Objective-C APIs in this C++ code of hotspot, but have been running into build issues. I am currently discussing those with people familiar with this area and plan to continue pursuing it further.

For those who are curious, the work in progress (untested) changes look like this 0d7f593

[jaikiran]

Do you think it's OK to go ahead with this integration?

I spoke to Alan about this and Alan says it's OK to do the os_bsd.cpp changes as a separate task. Alan also suggested that the long lines introduced in this PR could be shortened in length. I've updated the PR to address that. No other code changes. I will trigger a tier1, tier2 and tier3 testing with this change.

[jaikiran]

tier1, tier2 and tier3 testing in our CI with this change and tier1 testing on macOS 26 Beta has completed without any related issues. I'll need a re-review please to go ahead with the integration.

[jaikiran]

Thank you all for the reviews and inputs on this one.

[jaikiran]

/integrate

[openjdk]

Going to push as commit 8df6b2c.
Since your change was applied there have been 14 commits pushed to the master branch:

• ff24088: 8359919: Minor java.util.concurrent doc improvements
• 5a1301d: 8360548: Parallel: Remove outdated comments in MutableNUMASpace::bias_region
• 5039b42: 8359437: Make users and test suite not able to set LockingMode flag
• ... and 11 more: https://git.openjdk.org/jdk/compare/1fa090524a7c3bb5f2c92fb0f7217b9277ade9d9...master

Your commit was automatically rebased without conflicts.

[openjdk]

@jaikiran Pushed as commit 8df6b2c.

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

[jaikiran]

/backport :jdk25

[openjdk]

@jaikiran the backport was successfully created on the branch backport-jaikiran-8df6b2c4-jdk25 in my personal fork of openjdk/jdk. To create a pull request with this backport targeting openjdk/jdk:jdk25, just click the following link:

➡️ Create pull request

The title of the pull request is automatically filled in correctly and below you find a suggestion for the pull request body:

Hi all,

This pull request contains a backport of commit 8df6b2c4 from the openjdk/jdk repository.

The commit being backported was authored by Jaikiran Pai on 26 Jun 2025 and was reviewed by Roger Riggs, Lance Andersen and Kevin Rushforth.

Thanks!

If you need to update the source branch of the pull then run the following commands in a local clone of your personal fork of openjdk/jdk:

$ git fetch https://github.com/openjdk-bots/jdk.git backport-jaikiran-8df6b2c4-jdk25:backport-jaikiran-8df6b2c4-jdk25
$ git checkout backport-jaikiran-8df6b2c4-jdk25
# make changes
$ git add paths/to/changed/files
$ git commit --message 'Describe additional changes made'
$ git push https://github.com/openjdk-bots/jdk.git backport-jaikiran-8df6b2c4-jdk25

[jaikiran]

The few places where this misreporting of macOS version in os_bsd.cpp is going to impact is the VM error reporting (in hs_err files for example) and the output of the newly introduced -XX:+PrintJVMInfoAtExit option. So I think we can address this issue separately (I'll create a follow up issue to track that work).

I've created https://bugs.openjdk.org/browse/JDK-8360708 to track this.