FFI type mismatches in Rust for Linux
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At Kangrejos, Gary Guo wanted to discuss three problems with the way Rust and C code in the kernel interact: mismatched types, too many type casts, and the overhead of helper functions. To fix the first two problems, Guo proposed changing the way the kernel maps C types into Rust types. The last problem was a bit trickier, but he has a clever workaround for that, based on tricking the compiler into inlining the helper functions across language boundaries.
Currently, the Rust-for-Linux project uses uses bindgen to generate the bindings between C code and Rust code. This works, but not all types can be translated perfectly. Guo shared some slides to illustrate the current state of translated integers:
