HPCC-35956 Fix invalid c++ type generated for type_filepos

[ghalliday]

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Testing:

[ghalliday]

@dcamper see jira comments - I can't reproduce any longer.

[Copilot]

Pull request overview

Fixes incorrect C++ type generation for type_filepos by preventing generateType() from following the base type in that case.

Changes:

• Stop traversing the base type chain when handling type_filepos/type_blob in HqlCppWriter::generateType().

[Copilot]

The new next = nullptr; applies to both type_filepos and type_blob because of the shared fallthrough, but the comment only references type_filepos. This is misleading and makes it unclear whether blocking base-type traversal for type_blob is intentional. Consider either splitting the cases so only type_filepos sets next = nullptr, or updating the comment to reflect that both type_filepos and type_blob should not follow their base type.

Suggested change

	next = nullptr; // Do not follow the base type of a type_filepos
	next = nullptr; // Do not follow the base type of type_filepos or type_blob

[github-actions]

Jira Issue: https://hpccsystems.atlassian.net//browse/HPCC-35956

Jirabot Action Result:
Workflow Transition To: Merge Pending
Additional PR: #21072

[dcamper]

Looks good.