8294594: Fix cast-function-type warnings in signal handling code

[shipilev]

Need this to unblock MacOS compiler update in GHA.

Partially backports original openjdk/jdk@b06f1b1. There are lots of conflicts, because:

1. The original JDK-8294314 that added more verbose build warnings is not in 17u-dev yet.
2. The JDK-8292054 that added the /test/hotspot/gtest/runtime/test_signals.cpp is also not present in 17u-dev.

Additional testing:

• Linux AArch64 server fastdebug, all
• Linux x86_64 server fastdebug, all

---

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-8294594 needs maintainer approval

Issue

• JDK-8294594: Fix cast-function-type warnings in signal handling code (Bug - P4 - Approved)

Reviewers

• Martin Doerr (@TheRealMDoerr - Reviewer)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk17u-dev.git pull/4125/head:pull/4125
$ git checkout pull/4125

Update a local copy of the PR:
$ git checkout pull/4125
$ git pull https://git.openjdk.org/jdk17u-dev.git pull/4125/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 4125

View PR using the GUI difftool:
$ git pr show -t 4125

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk17u-dev/pull/4125.diff

Using Webrev

Link to Webrev Comment

[bridgekeeper]

👋 Welcome back shade! 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]

@shipilev 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:

8294594: Fix cast-function-type warnings in signal handling code

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 27 new commits pushed to the master branch:

• 9f89682: 8369506: Bytecode rewriting causes Java heap corruption on AArch64
• 98532ee: 8294591: Fix cast-function-type warning in TemplateTable
• dbfdc50: 8353832: Opensource FontClass, Selection and Icon tests
• ... and 24 more: https://git.openjdk.org/jdk17u-dev/compare/be5ae4cb0e9df4df3e07de2364359b442a42b184...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]

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

[mlbridge]

Webrevs

• 00: Full (c0a427bc)

[TheRealMDoerr]

LGTM. The fix is small and unlikely to cause trouble. And we need it for modern compiler support. So, thumbs up from my side.

[openjdk]

⚠️ @shipilev 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.

[shipilev]

/approval request Fixes another batch of warnings, which enables smoother compiler toolchain upgrades. Needed to unblock MacOS 15 upgrade in GHA. Patch does not apply cleanly, but conflicts are simple to resolve, see 17u PR. Passes all tests. Risk is low: eliminates some (odd) casts, no bug tail since initial integration several years ago.

[openjdk]

@shipilev
8294594: The approval request has been created successfully.

[shipilev]

Push approval granted. Here goes.

/integrate

[openjdk]

Going to push as commit a3442fd.
Since your change was applied there have been 27 commits pushed to the master branch:

• 9f89682: 8369506: Bytecode rewriting causes Java heap corruption on AArch64
• 98532ee: 8294591: Fix cast-function-type warning in TemplateTable
• dbfdc50: 8353832: Opensource FontClass, Selection and Icon tests
• ... and 24 more: https://git.openjdk.org/jdk17u-dev/compare/be5ae4cb0e9df4df3e07de2364359b442a42b184...master

Your commit was automatically rebased without conflicts.

[openjdk]

@shipilev Pushed as commit a3442fd.

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