Atomic Operations and Lock-Free Basics

Use C11 atomic types (_Atomic) to implement a lock-free counter.

Describe how compiler and processor instruction reordering can cause concurrency bugs.

Use memory barriers (fences) to enforce specific memory ordering guarantees.

Explain the concept of a compare-and-swap (CAS) operation and its role in optimistic concurrency.

Implement a simple lock-free stack using atomic compare-and-swap operations.

Analyze the challenges of the ABA problem in CAS-based algorithms.