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Date: Tue, 02 Apr 2024 12:49:58 +0000
To: Boqun Feng <boqun.feng@gmail.com>, rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org
From: Benno Lossin <benno.lossin@proton.me>
Cc: Miguel Ojeda <ojeda@kernel.org>, Alex Gaynor <alex.gaynor@gmail.com>, Wedson Almeida Filho <wedsonaf@gmail.com>, Gary Guo <gary@garyguo.net>, =?utf-8?Q?Bj=C3=B6rn_Roy_Baron?= <bjorn3_gh@protonmail.com>, Andreas Hindborg <a.hindborg@samsung.com>, Alice Ryhl <aliceryhl@google.com>, Martin Rodriguez Reboredo <yakoyoku@gmail.com>, Obei Sideg <linux@obei.io>
Subject: Re: [PATCH] rust: types: Make Opaque::get const
Message-ID: <512ad3fa-37d0-470e-9f4c-bd185d9b897f@proton.me>
In-Reply-To: <20240401214543.1242286-1-boqun.feng@gmail.com>
References: <20240401214543.1242286-1-boqun.feng@gmail.com>
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On 01.04.24 23:45, Boqun Feng wrote:
> To support a potential usage:
>=20
>      static foo: Opaque<Foo> =3D ..; // Or defined in an extern block.
>=20
>      ...
>=20
>      fn bar() {
>          let ptr =3D foo.get();
>      }
>=20
> `Opaque::get` need to be `const`, otherwise compiler will complain
> because calls on statics are limited to const functions.
>=20
> Also `Opaque::get` should be naturally `const` since it's a composition
> of two `const` functions: `UnsafeCell::get` and `ptr::cast`.
>=20
> Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
> ---
>   rust/kernel/types.rs | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)

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

--=20
Cheers,
Benno