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From: Wedson Almeida Filho <wedsonaf@gmail.com>
Date: Mon, 1 Apr 2024 20:21:45 -0300
Message-ID: <CANeycqra4O9hcKuoMXdh365iWr8KGE+BC2rBHn36mLOQGKY-kg@mail.gmail.com>
Subject: Re: [PATCH] rust: types: Make Opaque::get const
To: Boqun Feng <boqun.feng@gmail.com>
Cc: rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org, 
	Miguel Ojeda <ojeda@kernel.org>, Alex Gaynor <alex.gaynor@gmail.com>, Gary Guo <gary@garyguo.net>, 
	=?UTF-8?Q?Bj=C3=B6rn_Roy_Baron?= <bjorn3_gh@protonmail.com>, 
	Benno Lossin <benno.lossin@proton.me>, Andreas Hindborg <a.hindborg@samsung.com>, 
	Alice Ryhl <aliceryhl@google.com>, Martin Rodriguez Reboredo <yakoyoku@gmail.com>, Obei Sideg <linux@obei.io>
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On Mon, 1 Apr 2024 at 18:46, Boqun Feng <boqun.feng@gmail.com> wrote:
>
> To support a potential usage:
>
>     static foo: Opaque<Foo> = ..; // Or defined in an extern block.
>
>     ...
>
>     fn bar() {
>         let ptr = foo.get();
>     }
>
> `Opaque::get` need to be `const`, otherwise compiler will complain
> because calls on statics are limited to const functions.
>
> Also `Opaque::get` should be naturally `const` since it's a composition
> of two `const` functions: `UnsafeCell::get` and `ptr::cast`.
>
> Signed-off-by: Boqun Feng <boqun.feng@gmail.com>

Reviewed-by: Wedson Almeida Filho <walmeida@microsoft.com>