In-Depth Understanding of C++ Happens-Before: A Must for Advanced Concurrent Programmers
1. Introduction: Why is Happens-Before Necessary? In multithreaded programs, “statement order” ≠ “execution order”.Modern CPUs and compilers can reorder instructions as long as the results in a single thread remain unchanged, allowing for free optimization.However, in concurrent scenarios, this can lead to serious issues: bool ready = false;int data = 0; void writer() { data … Read more