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Message-ID: <1fad33a2-cba4-8ae9-0966-67ea24177149@asahilina.net>
Date:   Thu, 23 Mar 2023 21:24:31 +0900
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Subject: Re: [PATCH v2] rust: ioctl: Add ioctl number manipulation functions
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To:     Arnd Bergmann <arnd@arndb.de>, Miguel Ojeda <ojeda@kernel.org>,
        Alex Gaynor <alex.gaynor@gmail.com>,
        Wedson Almeida Filho <wedsonaf@gmail.com>,
        Boqun Feng <boqun.feng@gmail.com>, Gary Guo <gary@garyguo.net>,
        =?UTF-8?Q?Bj=c3=b6rn_Roy_Baron?= <bjorn3_gh@protonmail.com>
Cc:     linux-kernel@vger.kernel.org, rust-for-linux@vger.kernel.org,
        asahi@lists.linux.dev, Linux-Arch <linux-arch@vger.kernel.org>
References: <20230224-rust-ioctl-v2-1-5325e76a92df@asahilina.net>
 <56a3e16e-d686-440e-86b7-ee41f9d19fb1@app.fastmail.com>
From:   Asahi Lina <lina@asahilina.net>
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On 23/03/2023 21.18, Arnd Bergmann wrote:
> On Thu, Mar 23, 2023, at 13:08, Asahi Lina wrote:
>> Changes in v2:
>> - Changed from assert!() to build_assert!() (static_assert!() can't work here)
> ...
>> +/// Build an ioctl number, analogous to the C macro of the same name.
>> +const fn _IOC(dir: u32, ty: u32, nr: u32, size: usize) -> u32 {
>> +    core::assert!(dir <= bindings::_IOC_DIRMASK);
>> +    core::assert!(ty <= bindings::_IOC_TYPEMASK);
>> +    core::assert!(nr <= bindings::_IOC_NRMASK);
>> +    core::assert!(size <= (bindings::_IOC_SIZEMASK as usize));
> 
> Just to make sure: did you actually change it according
> to the changelog? It still looks like a runtime assertion
> to me, but I don't really understand any rust.

Umm... I'm not sure what happened there.

Sorry, I'll resend it. I ran into some unrelated pain with bindgen 
versions while trying to compile-test this, and along the way I must 
have somehow dropped the actual v2 change...

~~ Lina