Ramin_HAL9001, 1 year ago

Is it not possible for Rust to optimize out unused functions as with C?

No Rust can do dead code elimination. And I just checked, Rust can do indeed do FFI bindings from other languages when you ask the compiler to produce dynamically linking libraries, but I am guessing it has the same problems as Haskell when it produces .so or .dll files. In Haskell, things like “monad transformers” depend pretty heavily on function inlining in order to achieve good performance.

So I am talking more about how Rust makes use of the type system to make decisions about when to inline functions which is pretty important when it comes to performance. You usually can’t inline across module boundaries unless modules are all statically linked. So as I understand it, if you enable dynamic linking in your Rust program, you might see performance suffer a lot as compared to static linking, and this is why most Rust people (as I understand it) just make everything statically linked by default.