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Date:   Fri, 30 Jun 2023 17:32:53 +0200
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Subject: Re: [PATCH] rust: types: make `Opaque` be `!Unpin`
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To:     Benno Lossin <benno.lossin@proton.me>,
        Miguel Ojeda <ojeda@kernel.org>,
        Wedson Almeida Filho <wedsonaf@gmail.com>,
        Alex Gaynor <alex.gaynor@gmail.com>
Cc:     Boqun Feng <boqun.feng@gmail.com>, Gary Guo <gary@garyguo.net>,
        =?UTF-8?Q?Bj=c3=b6rn_Roy_Baron?= <bjorn3_gh@protonmail.com>,
        Alice Ryhl <aliceryhl@google.com>,
        Andreas Hindborg <nmi@metaspace.dk>,
        rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org,
        patches@lists.linux.dev
References: <20230630150216.109789-1-benno.lossin@proton.me>
From:   Alice Ryhl <alice@ryhl.io>
In-Reply-To: <20230630150216.109789-1-benno.lossin@proton.me>
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On 6/30/23 17:03, Benno Lossin wrote:
> Adds a `PhantomPinned` field to `Opaque<T>`. This removes the last Rust
> guarantee: the assumption that the type `T` can be freely moved. This is
> not the case for many types from the C side (e.g. if they contain a
> `struct list_head`). This change removes the need to add a
> `PhantomPinned` field manually to Rust structs that contain C structs
> which must not be moved.
> 
> Signed-off-by: Benno Lossin <benno.lossin@proton.me>

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