Starting with Rust 1.86.0 (currently in nightly, to be released on
2025-04-03), the `missing_abi` lint is warn-by-default [1]:

    error: extern declarations without an explicit ABI are deprecated
        --> rust/doctests_kernel_generated.rs:3158:1
         |
    3158 | extern {
         | ^^^^^^ help: explicitly specify the C ABI: `extern "C"`
         |
         = note: `-D missing-abi` implied by `-D warnings`
         = help: to override `-D warnings` add `#[allow(missing_abi)]`

Thus clean it up.

Link: https://github.com/rust-lang/rust/pull/132397 [1]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
 rust/kernel/init.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/rust/kernel/init.rs b/rust/kernel/init.rs
index 347049df556b..c962029f96e1 100644
--- a/rust/kernel/init.rs
+++ b/rust/kernel/init.rs
@@ -854,7 +854,7 @@ pub unsafe trait PinInit<T: ?Sized, E = Infallible>: Sized {
     /// use kernel::{types::Opaque, init::pin_init_from_closure};
     /// #[repr(C)]
     /// struct RawFoo([u8; 16]);
-    /// extern {
+    /// extern "C" {
     ///     fn init_foo(_: *mut RawFoo);
     /// }
     ///

base-commit: 100ceb4817a2ac650e29f107cf97161ce3e2289a
-- 
2.48.1

On Tue, Jan 21, 2025 at 9:10 PM Miguel Ojeda <ojeda@kernel.org> wrote:
>
> Starting with Rust 1.86.0 (currently in nightly, to be released on
> 2025-04-03), the `missing_abi` lint is warn-by-default [1]:
>
>     error: extern declarations without an explicit ABI are deprecated
>         --> rust/doctests_kernel_generated.rs:3158:1
>          |
>     3158 | extern {
>          | ^^^^^^ help: explicitly specify the C ABI: `extern "C"`
>          |
>          = note: `-D missing-abi` implied by `-D warnings`
>          = help: to override `-D warnings` add `#[allow(missing_abi)]`
>
> Thus clean it up.
>
> Link: https://github.com/rust-lang/rust/pull/132397 [1]
> Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Cc: <stable@vger.kernel.org> # Needed in 6.12.y only (Rust is pinned
in older LTSs).

And while there was nothing wrong back then with the commit, as usual:

    Fixes: 7f8977a7fe6d ("rust: init: add `{pin_}chain` functions to
`{Pin}Init<T, E>`")

Cheers,
Miguel