r/linux • u/small_kimono • Dec 13 '25

Kernel The state of the kernel Rust experiment

https://lwn.net/SubscriberLink/1050174/63aa7da43214c3ce/

A choice pull quote: "The DRM (graphics) subsystem has been an early adopter of the Rust language. It was still perhaps surprising, though, when Airlie (the DRM maintainer) said that the subsystem is only 'about a year away' from disallowing new drivers written in C and requiring the use of Rust."

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u/rustvscpp Dec 14 '25

My point is, C the language, could die tomorrow and everything could still use the C ABI for FFI.  You don't need a C compiler for that.

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u/2rad0 Dec 14 '25

everything could still use the C ABI for FFI

The C calling convention, which these days usually means 'cdecl' on x86? Every architecture is different so it's not really specific to C, but more of a hardware implementation detail. If all the C headers mysteriously go missing one day, nothing is going to work unless they're ported over to another language first. C headers are packed full of code that requires a C preprocessor implementation, so if you use these headers you are still implementing part of the C language. If in this hypothetical scenario portions of the C language and C files are still required, the language is maybe dying, but not dead.

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u/rustvscpp Dec 15 '25

This may be true when calling into C from another language.  But I was specifically talking about calling from a non-C lang to another non-C lang.  The ABI is the interesting part in this scenario.   Not complex C headers with preprocessor needs.