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Date:   Mon, 28 Mar 2022 21:01:13 +0200
From:   David Sterba <dsterba@suse.cz>
To:     Christoph Hellwig <hch@lst.de>
Cc:     Josef Bacik <josef@toxicpanda.com>,
        David Sterba <dsterba@suse.com>,
        Naohiro Aota <naohiro.aota@wdc.com>,
        linux-btrfs@vger.kernel.org
Subject: Re: [PATCH 1/2] btrfs: remove the zoned/zone_size union in struct
 btrfs_fs_info
Message-ID: <20220328190113.GS2237@twin.jikos.cz>
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References: <20220324165210.1586851-1-hch@lst.de>
 <20220324165210.1586851-2-hch@lst.de>
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On Thu, Mar 24, 2022 at 05:52:09PM +0100, Christoph Hellwig wrote:
> Reading a value from a different member of a union is not just a great
> way to obsfucate code, but also creates an aliasing violation.

Is it a violation in this case? Both are of the same type, violation
could be int/u64 and others but even in this case this is transparent to
the compiler and union cast is the cleanest way to access same bytes in
a structure. Anaywy now the helper btrfs_is_zoned is used everywhere
which abstracts the condition, which was the original idea for the
union.