Ramin_HAL9001, 1 year ago

The main difficulty I have with Rust (what prevents me from using it), is that the maintainers insist on statically compiling everything. This is fine for small programs, and even large monolithic applications that are not expected to change very often.

But for the machine learning projects I work on, I might want to include a single algorithm from a fairly large library of algorithms. The amount of memory used is not trivial, I am talking about the difference between loading a single algorithm in 50 MB of compiled code for a dynamically loadable library, versus loading the entire 1.5 GB library of algorithms of statically linked code just to use that one algorithm. Then when distributing this code to a few dozen compute nodes, that 50 MB versus 1.5 GB is suddenly a very noticeable difference.

There are other problems with statically linking everything as well, for example, if you want your application to be written in a high-level language like Python, TypeScript, or Lisp, you might want to have a library of Rust code that you can dynamically load into the Python interpreter and establish foreign function bindings to the Rust APIs. But this is not possible with statically linked code.

And as I understand, it is a difficult technical problem to solve. Apparently, in order for Rust to optimize a program and guarantee type safety and performance, it needs the type information in the source code. This type information is not normally stored into the dynamically loadable libraries (the .so or .dll files), so if you dynamically load a library into a Rust program its type safety and performance guarantees go out the window. So the Rust compiler developers have chosen to make everything as statically compiled as possible.

This is why I don’t see Rust replacing C any time soon. A language like Zig might have a better chance than Rust because it can produce dynamically loadable libraries that are fully ABI compatible with the libraries compiled by C compilers.