8368331: ClassFile Signature parsing fails for type parameter with no supertype

[liach]

Some type parameter declaration signatures in class and method generic signatures, such as <T:R:>, are valid per JVMS but are not accepted by either the ClassFile or the legacy core reflection parser. (Javac doesn't generate these because it always generates an Object upper bound) They can be constructed by the ClassFile API models. So it makes sense to support their parsing as supported by JVMS and our API model.

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Progress

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Issue

• JDK-8368331: ClassFile Signature parsing fails for type parameter with no supertype (Bug - P4)

Reviewers

• Adam Sotona (@asotona - Reviewer)

Reviewing

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[bridgekeeper]

👋 Welcome back liach! A progress list of the required criteria for merging this PR into pr/27380 will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[openjdk]

@liach This change now passes all automated pre-integration checks.

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After integration, the commit message for the final commit will be:

8368331: ClassFile Signature parsing fails for type parameter with no supertype

Reviewed-by: asotona

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At the time when this comment was updated there had been 7 new commits pushed to the master branch:

• 3036866: 8367972: ZGC: Reduce ZBarrierSet includes
• 3183a13: 8368073: PKCS11 HKDF can't use byte array IKM in FIPS mode
• 5350ce1: 8368373: Test H3MalformedResponseTest.testMalformedResponse intermittent timed out
• ... and 4 more: https://git.openjdk.org/jdk/compare/f1ee1b4a3d7c47b6f61b36b78504e3ec997a925a...master

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[mlbridge]

Webrevs

• 03: Full (e0c5c65f)
• 02: Full (0b1deef5)
• 01: Full - Incremental (0c4c58b6)
• 00: Full (0c4c58b6)

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The parent pull request that this pull request depends on has now been integrated and the target branch of this pull request has been updated. This means that changes from the dependent pull request can start to show up as belonging to this pull request, which may be confusing for reviewers. To remedy this situation, simply merge the latest changes from the new target branch into this pull request by running commands similar to these in the local repository for your personal fork:

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[asotona]

Looks good to me.

[ExE-Boss]

This makes it possible to denote T extends (ref or primitive) in a way which differentiates it from T extends ref Object.

[liach]

Thanks for the reviews!

/integrate

[openjdk]

Going to push as commit 1cd186c.
Since your change was applied there have been 13 commits pushed to the master branch:

• 0a64358: 8368273: LIBPTHREAD dependency is not needed for some jdk libs
• 727d41d: 8368226: Remove Thread.stop
• e8adc1f: 8367989: Remove InstanceKlass::allocate_objArray and ArrayKlass::allocate_arrayArray
• ... and 10 more: https://git.openjdk.org/jdk/compare/f1ee1b4a3d7c47b6f61b36b78504e3ec997a925a...master

Your commit was automatically rebased without conflicts.

[openjdk]

@liach Pushed as commit 1cd186c.

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

[ExE-Boss]

The JBS issue should probably link to JDK‑8351103.