Implement final MISRA C 2023 rule amendments

[MichaelRFairhurst]

Description

This covers all of the remaining rule amendments for MISRA C 2023.

Ideally for 18-6, we eventually support tss_t as an ObjectIdentity. However, it's a little tricky because currently ObjectIdentity extends Element, and a tss_t is already a VariableObjectIdentity (the tss_t object itself, not the thread storage it points to). So we can't simply override ObjectIdentity for tss_t objects to make a new thread local. Additionally, we could treat each tss_get() call as an ObjectIdentity but that diverges from the intention of the class, because the tss_get call doesn't identify the object, its the tss_t variable that identifies it.

We can open an issue and worry about that later if we wish. For now, we cover _Thread_local variables more comprehensively than tss_ts, which is probably A-OK.

Change request type

• Release or process automation (GitHub workflows, internal scripts)
• Internal documentation
• External documentation
• Query files (.ql, .qll, .qls or unit tests)
• External scripts (analysis report or other code shipped as part of a release)

Rules with added or modified queries

• No rules added
• Queries have been added for the following rules:
  • RULE-18-6 - new rule to handle new case (thread locals assigned to static storage duration objects)
• Queries have been modified for the following rules:
  • DIR-4-9
  • RULE-1-4,
  • RULE-21-12

Release change checklist

A change note (development_handbook.md#change-notes) is required for any pull request which modifies:

• The structure or layout of the release artifacts.
• The evaluation performance (memory, execution time) of an existing query.
• The results of an existing query in any circumstance.

If you are only adding new rule queries, a change note is not required.

Author: Is a change note required?

• Yes
• No

🚨🚨🚨
Reviewer: Confirm that format of shared queries (not the .qll file, the
.ql file that imports it) is valid by running them within VS Code.

• Confirmed

Reviewer: Confirm that either a change note is not required or the change note is required and has been added.

• Confirmed

Query development review checklist

For PRs that add new queries or modify existing queries, the following checklist should be completed by both the author and reviewer:

Author

• Have all the relevant rule package description files been checked in?
• Have you verified that the metadata properties of each new query is set appropriately?
• Do all the unit tests contain both "COMPLIANT" and "NON_COMPLIANT" cases?
• Are the alert messages properly formatted and consistent with the style guide?
• Have you run the queries on OpenPilot and verified that the performance and results are acceptable?
  As a rule of thumb, predicates specific to the query should take no more than 1 minute, and for simple queries be under 10 seconds. If this is not the case, this should be highlighted and agreed in the code review process.
• Does the query have an appropriate level of in-query comments/documentation?
• Have you considered/identified possible edge cases?
• Does the query not reinvent features in the standard library?
• Can the query be simplified further (not golfed!)

Reviewer

• Have all the relevant rule package description files been checked in?
• Have you verified that the metadata properties of each new query is set appropriately?
• Do all the unit tests contain both "COMPLIANT" and "NON_COMPLIANT" cases?
• Are the alert messages properly formatted and consistent with the style guide?
• Have you run the queries on OpenPilot and verified that the performance and results are acceptable?
  As a rule of thumb, predicates specific to the query should take no more than 1 minute, and for simple queries be under 10 seconds. If this is not the case, this should be highlighted and agreed in the code review process.
• Does the query have an appropriate level of in-query comments/documentation?
• Have you considered/identified possible edge cases?
• Does the query not reinvent features in the standard library?
• Can the query be simplified further (not golfed!)

Pull Request Overview

This PR implements the final amendments for MISRA C 2023 by updating change notes for several CodeQL queries.

• Updated change notes for DIR-4-9, clarifying that macros with _Generic are no longer reported
• Updated change notes for RULE-1-4, indicating the ban on usage of _Generics has been removed
• Added change notes for new query RULE-18-6 detecting thread local objects assigned to static storage duration objects, and updated notes for RULE-21-12 to report usage of certain functions in "fenv.h"

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[lcartey]

I'm fine with opening an issue to track extending this case.

[MichaelRFairhurst]

Filed #877