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Date:   Mon, 16 Jan 2023 22:07:36 +0000
From:   Gary Guo <gary@garyguo.net>
To:     Emilio Cobos =?UTF-8?B?w4FsdmFyZXo=?= <emilio@crisal.io>
Cc:     Wedson Almeida Filho <wedsonaf@gmail.com>,
        rust-for-linux@vger.kernel.org, Miguel Ojeda <ojeda@kernel.org>,
        Alex Gaynor <alex.gaynor@gmail.com>,
        Boqun Feng <boqun.feng@gmail.com>,
        =?UTF-8?B?QmrDtnJu?= Roy Baron <bjorn3_gh@protonmail.com>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 4/7] rust: sync: introduce `ArcBorrow`
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On Wed, 4 Jan 2023 17:06:50 +0100
Emilio Cobos =C3=81lvarez <emilio@crisal.io> wrote:

> Sorry for the drive-by comment, but maybe it saves some work.
>=20
> On 1/4/23 16:29, Wedson Almeida Filho wrote:
> > On Sat, 31 Dec 2022 at 19:43, Gary Guo <gary@garyguo.net> wrote: =20
> >>
> >> On Wed, 28 Dec 2022 06:03:43 +0000
> >> Wedson Almeida Filho <wedsonaf@gmail.com> wrote:
> >>> +pub struct ArcBorrow<'a, T: ?Sized + 'a> {
> >>> +    inner: NonNull<ArcInner<T>>,
> >>> +    _p: PhantomData<&'a ()>,
> >>> +}
> >>> +
> >>> +impl<T: ?Sized> Clone for ArcBorrow<'_, T> {
> >>> +    fn clone(&self) -> Self {
> >>> +        *self
> >>> +    }
> >>> +}
> >>> +
> >>> +impl<T: ?Sized> Copy for ArcBorrow<'_, T> {} =20
> >>
> >> Couldn't this just be derived `Clone` and `Copy`? =20
> >=20
> > Indeed. I'll send a v2 with this. =20
>=20
> I'm not sure this is true. Deriving will add the T: Copy and T: Clone=20
> bound, which I think is not what you want here.
>=20
> i.e., I assume you want an ArcBorrow to be Copy even if the underlying T=
=20
> is not.

Thanks for pointing out, I neglected that.

In this case:

Reviewed-by: Gary Guo <gary@garyguo.net>