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Message-ID: <928d9094-db54-7b27-98a6-9ece514f12e1@kernel.dk>
Date:   Tue, 15 Nov 2022 16:09:29 -0700
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Subject: Re: [PATCH v1 2/2] io_uring: uapi: Don't use a zero-size array
To:     Ammar Faizi <ammarfaizi2@gnuweeb.org>
Cc:     Pavel Begunkov <asml.silence@gmail.com>,
        Stefan Metzmacher <metze@samba.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        io-uring Mailing List <io-uring@vger.kernel.org>,
        GNU/Weeb Mailing List <gwml@vger.gnuweeb.org>
References: <20221115212614.1308132-1-ammar.faizi@intel.com>
 <20221115212614.1308132-3-ammar.faizi@intel.com>
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From:   Jens Axboe <axboe@kernel.dk>
In-Reply-To: <20221115212614.1308132-3-ammar.faizi@intel.com>
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On 11/15/22 2:29 PM, Ammar Faizi wrote:
> From: Ammar Faizi <ammarfaizi2@gnuweeb.org>
> 
> Don't use a zero-size array because it doesn't allow the user to
> compile an app that uses liburing with the `-pedantic-errors` flag:
> 
>   io_uring.h:611:28: error: zero size arrays are an extension [-Werror,-Wzero-length-array]
> 
> Replace the array size from 0 to 1.
> 
>   - No functional change is intended.
>   - No struct/union size change.

The only reason why they don't grow the struct, is because it's in
a union. I don't like this patch, as the zero sized array is a clear
sign that this struct has data past it. If it's a single entry, that's
very different.

Yes that apparently makes pendantic errors unhappy, but I care more
about the readability of it.

-- 
Jens Axboe