8335688: Fix -Wzero-as-null-pointer-constant warnings from fflush calls in jvmti tests

[kimbarrett]

Please review this change to some jvmti tests, which were calling fflush with
an argument of 0. Most of these are in C++ code, where we change them to use
nullptr as the argument. A couple are in C, where we change them to use NULL.
This removes a bunch of -Wzero-as-null-pointer-constant when building with
that enabled.

Testing: mach5 tier1

---

Progress

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Issue

• JDK-8335688: Fix -Wzero-as-null-pointer-constant warnings from fflush calls in jvmti tests (Enhancement - P4)

Reviewers

• Julian Waters (@TheShermanTanker - Committer)
• Coleen Phillimore (@coleenp - Reviewer)

Reviewing

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$ git checkout pull/20032

Update a local copy of the PR:
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$ git pull https://git.openjdk.org/jdk.git pull/20032/head

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$ git pr checkout 20032

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[bridgekeeper]

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[openjdk]

@kimbarrett 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:

8335688: Fix -Wzero-as-null-pointer-constant warnings from fflush calls in jvmti tests

Reviewed-by: jwaters, coleenp

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 50 new commits pushed to the master branch:

• 0e0dfca: 8330806: test/hotspot/jtreg/compiler/c1/TestLargeMonitorOffset.java fails on ARM32
• f3ff4f7: 8335882: platform/cgroup/TestSystemSettings.java fails on Alpine Linux
• 8f62f31: 8335906: [s390x] Test Failure: GTestWrapper.java
• 2a29647: 8334777: Test javax/management/remote/mandatory/notif/NotifReconnectDeadlockTest.java failed with NullPointerException
• 564a72e: 8335955: JDK-8335742 wrongly used a "JDK-" prefix in the problemlist bug number
• 9c7a6ea: 8312125: Refactor CDS enum class handling
• bb1f8a1: 8335904: Fix invalid comment in ShenandoahLock
• babf6df: 8334757: AssertionError: Missing type variable in where clause
• 3733fe3: 8335789: [TESTBUG] XparColor.java test fails with Error. Parse Exception: Invalid or unrecognized bugid: @
• 3a87eb5: 8335126: Shenandoah: Improve OOM handling
• ... and 40 more: https://git.openjdk.org/jdk/compare/3efa93ba1307cedf05609c0c04b2ba986a515f6e...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]

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[mlbridge]

Webrevs

• 00: Full (ee84bfc1)

[coleenp]

Looks good.

[kimbarrett]

Thanks for reviews @TheShermanTanker and @coleenp

[kimbarrett]

/integrate

[openjdk]

Going to push as commit 7e11fb7.
Since your change was applied there have been 51 commits pushed to the master branch:

• 531a6d8: 8335911: Document ccls indexer in doc/ide.md
• 0e0dfca: 8330806: test/hotspot/jtreg/compiler/c1/TestLargeMonitorOffset.java fails on ARM32
• f3ff4f7: 8335882: platform/cgroup/TestSystemSettings.java fails on Alpine Linux
• 8f62f31: 8335906: [s390x] Test Failure: GTestWrapper.java
• 2a29647: 8334777: Test javax/management/remote/mandatory/notif/NotifReconnectDeadlockTest.java failed with NullPointerException
• 564a72e: 8335955: JDK-8335742 wrongly used a "JDK-" prefix in the problemlist bug number
• 9c7a6ea: 8312125: Refactor CDS enum class handling
• bb1f8a1: 8335904: Fix invalid comment in ShenandoahLock
• babf6df: 8334757: AssertionError: Missing type variable in where clause
• 3733fe3: 8335789: [TESTBUG] XparColor.java test fails with Error. Parse Exception: Invalid or unrecognized bugid: @
• ... and 41 more: https://git.openjdk.org/jdk/compare/3efa93ba1307cedf05609c0c04b2ba986a515f6e...master

Your commit was automatically rebased without conflicts.

[openjdk]

@kimbarrett Pushed as commit 7e11fb7.

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