I have a number of negative stereotypes associated with Rust and Rust programmers that I am trying to set aside right now and just look at this from a technical perspective. Has the Rust-portability situation been addressed? Or will this change restrict the number of platforms the Linux kernel will be usable on? Assuming that is the case (I remember reading that GCC will acquire Rust support), what will the advantages be? I would guess stability might improve due to more static analysis, but what about performance? Build-time? And will this have any effect on Rust?

The rust portability story is in the process of being addressed, by two different projects:

gcc-rs[0] adds a Rust frontend to GCC.

rustc-codegen-gcc[1] adds a GCC backend to rustc.

Both are progressing pretty well, but it will likely still take a while until they reach maturity.

> Or will this change restrict the number of platforms the Linux kernel will be usable on?

There won't be any Rust inside the Linux core, only for drivers. So no, the linux kernel will always be usable on all platforms. However, the drivers written in Rust won't be usable on platforms not supported by LLVM until a GCC alternative becomes mature.

> what will the advantages be?

There are multiple: Safety, improved stability, and developer productivity. Compile time will likely take a hit (Rust is famously slow to compile), but I don't expect a big shift in runtime performance (could be slightly better due to the extra opportunities the compiler has for optimization, but it's not super likely).

As for having any effects on Rust: it already has! A lot of unstable features got prioritized due to being necessary for the kernel, such as fallible allocations.

[0]: https://github.com/Rust-GCC/gccrs - monthly reports at https://thephilbert.io/category/gccrs-status-updates/

[1]: https://github.com/rust-lang/rustc_codegen_gcc - monthly reports at https://blog.antoyo.xyz/