Re: [PATCH v2 1/3] kbuild: rust: add `CONFIG_RUSTC_CLANG_LLVM_COMPATIBLE`

[Andreas Hindborg]

"Gary Guo" <gary@xxxxxxxxxxx> writes:

> This config detects if Rust and Clang have matching LLVM major version.
> All IR or bitcode operations (e.g. LTO) rely on LLVM major version to be
> matching, otherwise it may generate errors, or worse, miscompile silently
> due to change of IR semantics.
>
> It's usually suggested to use the exact same LLVM version, but this can
> be difficult to guarantee. Rust's suggestion [1] is also major-version only,
> so I think this check is sufficient for the kernel.
>
> Link: https://doc.rust-lang.org/rustc/linker-plugin-lto.html [1]
> Signed-off-by: Gary Guo <gary@xxxxxxxxxxx>


Reviewed-by: Andreas Hindborg <a.hindborg@xxxxxxxxxx>


Best regards,
Andreas Hindborg