8351889: C2 crash: assertion failed: Base pointers must match (addp 344)

[rwestrel]

Hi all,

This pull request contains a backport of commit ad29642d from the openjdk/jdk repository.

The commit being backported was authored by Roland Westrelin on 15 Dec 2025 and was reviewed by Roberto Castañeda Lozano and Emanuel Peter.

Thanks!

---

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

Issue

• JDK-8351889: C2 crash: assertion failed: Base pointers must match (addp 344) (Bug - P3)

Reviewers

• Roberto Castañeda Lozano (@robcasloz - Reviewer)
• Tobias Hartmann (@TobiHartmann - Reviewer)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk.git pull/28893/head:pull/28893
$ git checkout pull/28893

Update a local copy of the PR:
$ git checkout pull/28893
$ git pull https://git.openjdk.org/jdk.git pull/28893/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 28893

View PR using the GUI difftool:
$ git pr show -t 28893

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk/pull/28893.diff

Using Webrev

Link to Webrev Comment

[bridgekeeper]

👋 Welcome back roland! A progress list of the required criteria for merging this PR into jdk26 will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[openjdk]

@rwestrel 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:

8351889: C2 crash: assertion failed:  Base pointers must match (addp 344)

Reviewed-by: rcastanedalo, thartmann

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 16 new commits pushed to the jdk26 branch:

• 9ba5d6f: 8374433: java/util/Locale/PreserveTagCase.java does not run any tests
• 0981794: 8374642: EscapeHash macro fails with GNU make 4.3 and 4.4
• 867f462: 8374210: [BACKOUT] Move input validation checks to Java for java.lang.StringCoding intrinsics
• ... and 13 more: https://git.openjdk.org/jdk/compare/6950503dcf786e875a75c76141759e24ac46c3f4...jdk26

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 jdk26 branch, type /integrate in a new comment.

[openjdk]

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

[openjdk]

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

• hotspot

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 (acd2913c)
• 00: Full (ff20d122)

[robcasloz]

Running internal tests, will come back with results.

[robcasloz]

Test results look good!

[rwestrel]

@robcasloz thanks for testing and approval. I merge with latest. Do you need to rerun testing?

[TobiHartmann]

Roberto is still on vacation. I think we are good here. Ship it!

[rwestrel]

/integrate

[openjdk]

Going to push as commit e0f1c3a.
Since your change was applied there have been 16 commits pushed to the jdk26 branch:

• 9ba5d6f: 8374433: java/util/Locale/PreserveTagCase.java does not run any tests
• 0981794: 8374642: EscapeHash macro fails with GNU make 4.3 and 4.4
• 867f462: 8374210: [BACKOUT] Move input validation checks to Java for java.lang.StringCoding intrinsics
• ... and 13 more: https://git.openjdk.org/jdk/compare/6950503dcf786e875a75c76141759e24ac46c3f4...jdk26

Your commit was automatically rebased without conflicts.

[openjdk]

@rwestrel Pushed as commit e0f1c3a.

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