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0 pointsdeckarep8y ago0 comments

I’m pretty sure Rust saves you from ALL data races so long as you stay within the boundaries of safe code. Do you have anything at all to reference otherwise that says only certain data races are detected while others are not?

To my knowledge you can defeat the compile-time data race detection if you are either doing unsafe or certain scenarios with Cell/RefCell but even in that case you are guaranteed runtime detection rather than compile time detection.

These feature alone is worth its weight in gold.

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s17n8y ago

Given the a "data race" is essentially defined to be the class of races that Rust's type system guards again, yeah it saves you from all of them.

kibwen8y ago

Rust's definition of "data race" isn't just "what the Rust compiler rejects", it has a specific meaning:

"Safe Rust guarantees an absence of data races, which are defined as: 1. two or more threads concurrently accessing a location of memory, 2. one of them is a write, 3. one of them is unsynchronized."

https://doc.rust-lang.org/nomicon/races.html

Argorak8y ago

qznc puts that better then I do. It saves you from data races, but not from race conditions.

Cell and RefCell are both not Sync (that means they can't be used from multiple threads) for a reason. RefCell does, however, allow borrow checking at runtime, for wrapping it with something that establishes Sync.

j / k navigate · click thread line to collapse