Re: [PATCH 6/6] scripts: generate_rust_analyzer: move sysroot crates to sysroot_project

[Jesung Yang]

On Wed Jan 21, 2026 at 12:34 AM KST, Tamir Duberstein wrote:
> On Tue, Jan 20, 2026 at 3:55 AM Eliot Courtney <ecourtney@xxxxxxxxxx> wrote:
>>
>> Use rust-analyzer's sysroot_project feature to properly configure
>> sysroot crates (core, alloc, std, proc_macro). This allows
>> rust-analyzer to correctly resolve items from the sysroot and
>> automatically add sysroot crate dependencies to all project crates.
>>
>> Some sysroot crates use #[path] directives to load files outside of
>> their directory but still in the sysroot. This is disallowed by
>> rust-analyzer, so the sysroot crate are not properly loaded. Loading them
>> using sysroot_project tells rust-analyzer to let them load anything inside
>> sysroot_src.
>>
>> The sysroot_project field was added to rust-analyzer in v0.3.2328
>> (~1.87.0) and is silently ignored by older versions. In that case,
>> rust-analyzer falls back to loading the sysroot via sysroot_src.
>> This basically works, but the advantage of using sysroot_project is
>> that we can make the set of features/cfgs more similar to what the
>> actual build uses.
>
> This is a very nice patch, and perhaps obviates the need for the
> versioning infrastructure in
> https://lore.kernel.org/all/20260109-ra-fix-primitive-v2-0-249852a4145a@xxxxxxxxx/.

I still think the versioning infrastructure is a prerequisite as we're
using the `sysroot_src` field here.

If we specify `sysroot_src` without `crate_attrs = ["no_std"]`,
rust-analyzer treats `std` as a dependency for all local crates by
default. Consequently, any rust-analyzer version lacking `crate_attrs`
support (which silently ignores `crate_attrs = ["no_std"]`) would
incorrectly assume an implicit `std` dependency for all kernel modules.
Having the versioning infrastructure first allows us to handle this
transition without breaking the user experience for those on older
toolchains.

Best regards,
Jesung