las3_pub / predictable_parallel_patterns

Make sure that the guard page leads to sigsegv as expected.

Everything so far is untested. We only made sure tha fast path still seems to function correctly. Next up is writing tests for both the fast and slow path to then introduce the slow path. After that we can look at performance optimizations.

This allows us to more easily handle them and makes their interface closer to std::thread.

We do this to properly separate the cache alginment logic in the next step, allowing us to port all cache aligned objects without worrying about portability.