In the upcoming Rust 1.78.0, Clippy suggests to implement `Default` even
when `new()` is `const`, since `Default::default()` may call `const`
functions even if it is not `const` itself [1]:

    error: you should consider adding a `Default` implementation for `LockClassKey`
      --> rust/kernel/sync.rs:31:5
       |
    31 | /     pub const fn new() -> Self {
    32 | |         Self(Opaque::uninit())
    33 | |     }
       | |_____^

Thus implement it.

Link: https://github.com/rust-lang/rust-clippy/pull/10903 [1]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
 rust/kernel/sync.rs | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/rust/kernel/sync.rs b/rust/kernel/sync.rs
index c983f63fd56e..0ab20975a3b5 100644
--- a/rust/kernel/sync.rs
+++ b/rust/kernel/sync.rs
@@ -37,6 +37,12 @@ pub(crate) fn as_ptr(&self) -> *mut bindings::lock_class_key {
     }
 }
 
+impl Default for LockClassKey {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
 /// Defines a new static lock class and returns a pointer to it.
 #[doc(hidden)]
 #[macro_export]
-- 
2.44.0

On 01.04.24 23:23, Miguel Ojeda wrote:
> In the upcoming Rust 1.78.0, Clippy suggests to implement `Default` even
> when `new()` is `const`, since `Default::default()` may call `const`
> functions even if it is not `const` itself [1]:
> 
>      error: you should consider adding a `Default` implementation for `LockClassKey`
>        --> rust/kernel/sync.rs:31:5
>         |
>      31 | /     pub const fn new() -> Self {
>      32 | |         Self(Opaque::uninit())
>      33 | |     }
>         | |_____^
> 
> Thus implement it.
> 
> Link: https://github.com/rust-lang/rust-clippy/pull/10903 [1]
> Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
> ---
>   rust/kernel/sync.rs | 6 ++++++
>   1 file changed, 6 insertions(+)

Reviewed-by: Benno Lossin <benno.lossin@proton.me>

-- 
Cheers,
Benno

On Mon, Apr 1, 2024 at 11:23 PM Miguel Ojeda <ojeda@kernel.org> wrote:
>
> In the upcoming Rust 1.78.0, Clippy suggests to implement `Default` even
> when `new()` is `const`, since `Default::default()` may call `const`
> functions even if it is not `const` itself [1]:
>
>     error: you should consider adding a `Default` implementation for `LockClassKey`
>       --> rust/kernel/sync.rs:31:5
>        |
>     31 | /     pub const fn new() -> Self {
>     32 | |         Self(Opaque::uninit())
>     33 | |     }
>        | |_____^
>
> Thus implement it.
>
> Link: https://github.com/rust-lang/rust-clippy/pull/10903 [1]
> Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Reviewed-by: Alice Ryhl <aliceryhl@google.com>

On Mon, Apr 01, 2024 at 11:23:01PM +0200, Miguel Ojeda wrote:
> In the upcoming Rust 1.78.0, Clippy suggests to implement `Default` even
> when `new()` is `const`, since `Default::default()` may call `const`
> functions even if it is not `const` itself [1]:
> 
>     error: you should consider adding a `Default` implementation for `LockClassKey`
>       --> rust/kernel/sync.rs:31:5
>        |
>     31 | /     pub const fn new() -> Self {
>     32 | |         Self(Opaque::uninit())
>     33 | |     }
>        | |_____^
> 
> Thus implement it.
> 
> Link: https://github.com/rust-lang/rust-clippy/pull/10903 [1]
> Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Reviewed-by: Boqun Feng <boqun.feng@gmail.com>

Regards,
Boqun

> ---
>  rust/kernel/sync.rs | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/rust/kernel/sync.rs b/rust/kernel/sync.rs
> index c983f63fd56e..0ab20975a3b5 100644
> --- a/rust/kernel/sync.rs
> +++ b/rust/kernel/sync.rs
> @@ -37,6 +37,12 @@ pub(crate) fn as_ptr(&self) -> *mut bindings::lock_class_key {
>      }
>  }
>  
> +impl Default for LockClassKey {
> +    fn default() -> Self {
> +        Self::new()
> +    }
> +}
> +
>  /// Defines a new static lock class and returns a pointer to it.
>  #[doc(hidden)]
>  #[macro_export]
> -- 
> 2.44.0
>