Fix pthread_t aliasing with pthread_create

[maxwellpirtle]

Overview

As we discussed, I was worried about the possibility of pthread_t confusing the model. Simply using the runner_id_t assigned uniquely to each thread is a better strategy here and we can avoid using the pthread_t handles altogether in the model (which is a better design anyway).

Summary by CodeRabbit

• New Features

  • Added a recycled-thread example demonstrating repeated worker-thread creation and cleanup.
  • Updated example applications to link with the library.

• Bug Fixes

  • Improved thread tracking when thread descriptors are reused.
  • Thread creation now validates and propagates stable runner IDs, improving scheduling and checkpoint restoration reliability.
  • Runner observations now consistently use model-assigned IDs.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro Plus

Run ID: fa0fbbec-1c41-41a8-90ea-7804bae170e7

📥 Commits

Reviewing files that changed from the base of the PR and between 7a2d504 and 05fd24b.

📒 Files selected for processing (7)

• include/mcmini/coordinator/model_to_system_map.hpp
• src/examples/CMakeLists.txt
• src/examples/recycled-thread.c
• src/lib/wrappers.c
• src/mcmini/coordinator/coordinator.cpp
• src/mcmini/mcmini.cpp
• src/mcmini/model/transitions/thread.cpp

---

📝 Walkthrough

Walkthrough

The change replaces pthread_t-address runner identification with model-assigned runner IDs. Thread wrappers publish IDs to the scheduler, coordinator observation validates them, and a recycled-thread example demonstrates repeated thread creation.

Changes

Runner ID observation flow

Layer / File(s)	Summary
Runner observation contract include/mcmini/coordinator/model_to_system_map.hpp, src/mcmini/coordinator/coordinator.cpp	Runner observation now accepts runner IDs, returns void, removes address-based lookup, and raises an error when model and target IDs differ.
Thread runner ID propagation src/lib/wrappers.c, src/mcmini/mcmini.cpp, src/mcmini/model/transitions/thread.cpp	Thread creation arguments carry the child runner ID. The wrapper publishes and validates the ID before sending it to the scheduler.
Recycled-thread example src/examples/CMakeLists.txt, src/examples/recycled-thread.c	The build adds the recycled-thread executable and links the examples with libmcmini. The example creates and joins threads across three rounds.

Estimated code review effort: 3 (Moderate) | ~20 minutes

Sequence Diagram(s)

sequenceDiagram
  participant ThreadWrapper
  participant Scheduler
  participant Coordinator
  ThreadWrapper->>ThreadWrapper: Publish child runner ID
  ThreadWrapper->>Scheduler: Send runner ID
  Scheduler->>Coordinator: Observe runner
  Coordinator->>Coordinator: Validate runner ID

Loading

Possibly related PRs

• mcminickpt/deep-debug#11: Related thread-wrapper and runner-ID handling in src/lib/wrappers.c.

Suggested labels: bug

Suggested reviewers: gc00, aayushi363

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly describes the primary change: replacing unsafe pthread_t handling in pthread_create with runner IDs.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands.}