8374168: Resolve disabled warnings in JDWP agent

[alexmenkov]

The fix resolves disabled warnings in debugger agent

---

Progress

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Issue

• JDK-8374168: Resolve disabled warnings in JDWP agent (Sub-task - P4)

Reviewers

• Chris Plummer (@plummercj - Reviewer)
• Serguei Spitsyn (@sspitsyn - Reviewer)
• Erik Joelsson (@erikj79 - Reviewer) Review applies to 8548586d

Reviewers without OpenJDK IDs

• @khanbilal732 (no known openjdk.org user name / role) Review applies to 339229c2

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[bridgekeeper]

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[openjdk]

@alexmenkov 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:

8374168: Resolve disabled warnings in JDWP agent

Reviewed-by: cjplummer, sspitsyn, erikj

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At the time when this comment was updated there had been 84 new commits pushed to the master branch:

• a59dbc5: 8373475: Unintentional format string in logString of AccessInfo.cpp
• 72e1e15: 8373474: 2 Unintentional format string defect groups in jabswitch.cpp
• f5249db: 8374233: Overloaded constructor MountUnmountDisabler(jthread thread) is missed
• ... and 81 more: https://git.openjdk.org/jdk/compare/87d881fee01c42f5847031a63d50873b3d438f7a...master

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[openjdk]

@alexmenkov The following labels will be automatically applied to this pull request:

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[mlbridge]

Webrevs

• 05: Full - Incremental (30fbc50a)
• 04: Full - Incremental (64ca8bbb)
• 03: Full - Incremental (8548586d)
• 02: Full - Incremental (35ccaf32)
• 01: Full - Incremental (79cfd6e3)
• 00: Full (339229c2)

[sspitsyn]

Looks good. Posted one nit.

[plummercj]

Can you explain the need for this. These types are all naturally jints, so I'm not sure why you would need to cast them here.

[alexmenkov]

These are enums (i.e. ints) , GHA on Windows fail because they are 3 different enum types (warning 5287)
For unknown reason (different MSVC version maybe) my local Windows build and our CI passed

[plummercj]

These are enums (i.e. ints) , GHA on Windows fail because they are 3 different enum types (warning 5287)
For unknown reason (different MSVC version maybe) my local Windows build and our CI passed

This code that we have elsewhere in the debug agent seems to compile ok. Perhaps all that is needed is a cast of JVMTI_VERSION to jint:

static jboolean isVersionGte12x() {
    jint version;
    jvmtiError err =
        JVMTI_FUNC_PTR(gdata->jvmti,GetVersionNumber)(gdata->jvmti, &version);

    if (err == JVMTI_ERROR_NONE) {
        jint major, minor;

        major = (version & JVMTI_VERSION_MASK_MAJOR)
                    >> JVMTI_VERSION_SHIFT_MAJOR;
        minor = (version & JVMTI_VERSION_MASK_MINOR)
                    >> JVMTI_VERSION_SHIFT_MINOR;
        return (major > 1 || (major == 1 && minor >= 2)) ? JNI_TRUE : JNI_FALSE;
    } else {
        return JNI_FALSE;
    }
}

[kimbarrett]

Similarly, no warnings for JvmtiExport::decode_version_values()

jdk/src/hotspot/share/prims/jvmtiExport.cpp

Lines 643 to 648 in e1d81c0

	JvmtiExport::decode_version_values(jint version, int * major, int * minor,
	int * micro) {
	*major = (version & JVMTI_VERSION_MASK_MAJOR) >> JVMTI_VERSION_SHIFT_MAJOR;
	*minor = (version & JVMTI_VERSION_MASK_MINOR) >> JVMTI_VERSION_SHIFT_MINOR;
	*micro = (version & JVMTI_VERSION_MASK_MICRO) >> JVMTI_VERSION_SHIFT_MICRO;
	}

where the version is a jint.
And jint does seem like the natural type here.

[sspitsyn]

Thank you for the updates. Looks good.

[erikj79]

Build change looks good.

[alexmenkov]

With the latest version GHA Windows-x64 build still fails:
debugInit.c
d:\a\jdk\jdk\src\jdk.jdwp.agent\share\native\libjdwp\debugInit.c(184): error C2220: the following warning is treated as an error
d:\a\jdk\jdk\src\jdk.jdwp.agent\share\native\libjdwp\debugInit.c(184): warning C5287: operands are different enum types '<unnamed-enum-JVMTI_VERSION_1>' and '<unnamed-enum-JVMTI_VERSION_MASK_INTERFACE_TYPE>'; use an explicit cast to silence this warning
d:\a\jdk\jdk\src\jdk.jdwp.agent\share\native\libjdwp\debugInit.c(184): note: to simplify migration, consider the temporary use of /Wv:18 flag with the version of the compiler with which you used to build without warnings
d:\a\jdk\jdk\src\jdk.jdwp.agent\share\native\libjdwp\debugInit.c(186): warning C5287: operands are different enum types '<unnamed-enum-JVMTI_VERSION_1>' and '<unnamed-enum-JVMTI_VERSION_MASK_INTERFACE_TYPE>'; use an explicit cast to silence this warning
d:\a\jdk\jdk\src\jdk.jdwp.agent\share\native\libjdwp\debugInit.c(186): note: to simplify migration, consider the temporary use of /Wv:18 flag with the version of the compiler with which you used to build without warnings
d:\a\jdk\jdk\src\jdk.jdwp.agent\share\native\libjdwp\debugInit.c(188): warning C5287: operands are different enum types '<unnamed-enum-JVMTI_VERSION_1>' and '<unnamed-enum-JVMTI_VERSION_MASK_INTERFACE_TYPE>'; use an explicit cast to silence this warning
d:\a\jdk\jdk\src\jdk.jdwp.agent\share\native\libjdwp\debugInit.c(188): note: to simplify migration, consider the temporary use of /Wv:18 flag with the version of the compiler with which you used to build without warnings

[alexmenkov]

Looks like this is a bug in MSVC: https://developercommunity.visualstudio.com/t/warning-C5287:-operands-are-different-e/10877942
cast to signed 32bit integer does not silence the warning.
I think the simplest would be to cast to unsigned int