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Date:   Fri, 2 Dec 2022 18:32:47 +0000
From:   Wei Liu <wei.liu@kernel.org>
To:     ojeda@kernel.org
Cc:     Wedson Almeida Filho <wedsonaf@gmail.com>,
        Alex Gaynor <alex.gaynor@gmail.com>,
        Boqun Feng <boqun.feng@gmail.com>, Gary Guo <gary@garyguo.net>,
        =?iso-8859-1?Q?Bj=F6rn?= Roy Baron <bjorn3_gh@protonmail.com>,
        rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org,
        patches@lists.linux.dev, Wei Liu <wei.liu@kernel.org>
Subject: Re: [PATCH v2 26/28] rust: build_assert: add `build_{error,assert}!`
 macros
Message-ID: <Y4pEzzSs9vO7cvjT@liuwe-devbox-debian-v2>
References: <20221202161502.385525-1-ojeda@kernel.org>
 <20221202161502.385525-27-ojeda@kernel.org>
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On Fri, Dec 02, 2022 at 05:14:57PM +0100, ojeda@kernel.org wrote:
> From: Gary Guo <gary@garyguo.net>
> 
> Add the `build_error!` and `build_assert!` macros which leverage
> the previously introduced `build_error` crate. Do so in a new
> module, called `build_assert`.
> 
> The former fails the build if the code path calling it can possibly
> be executed. The latter asserts that a boolean expression is `true`
> at compile time.
> 
> In particular, `build_assert!` can be used in some contexts where
> `static_assert!` cannot:
> 
>     fn f1<const N: usize>() {
>         static_assert!(N > 1);` // Error.
>         build_assert!(N > 1);   // Build-time check.
>         assert!(N > 1);         // Run-time check.
>     }
> 
>     #[inline]
>     fn f2(n: usize) {
>         static_assert!(n > 1);  // Error.
>         build_assert!(n > 1);   // Build-time check.
>         assert!(n > 1);         // Run-time check.
>     }
> 
> Signed-off-by: Gary Guo <gary@garyguo.net>
> [Reworded, adapted for upstream and applied latest changes]
> Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Reviewed-by: Wei Liu <wei.liu@kernel.org>