"Safe Rust guarantees an absence of data races, which are defined as: two or more threads concurrently accessing a location of memory, where one or more of them is a write, and one or more of them is unsynchronized. A data race has Undefined Behavior, and is therefore impossible to perform in Safe Rust. [...] However Rust does not prevent general race conditions. This is mathematically impossible in situations where you do not control the scheduler, which is true for the normal OS environment. [...] For this reason, it is considered "safe" for Rust to get deadlocked or do something nonsensical with incorrect synchronization: this is known as a general race condition or resource race. Obviously such a program isn't very good, but Rust of course cannot prevent all logic errors. In any case, a race condition cannot violate memory safety in a Rust program on its own. Only in conjunction with some other unsafe code can a race condition actually violate memory safety."