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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Mon, 28 Feb 2022 12:10:24 -0800
Message-ID: <CAHk-=wiTCvLQkHcJ3y0hpqH7FEk9D28LDvZZogC6OVLk7naBww@mail.gmail.com>
Subject: Re: [PATCH 2/6] treewide: remove using list iterator after loop body
 as a ptr
To:     =?UTF-8?Q?Christian_K=C3=B6nig?= <christian.koenig@amd.com>
Cc:     Jakob Koschel <jakobkoschel@gmail.com>,
        alsa-devel@alsa-project.org, linux-aspeed@lists.ozlabs.org,
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On Mon, Feb 28, 2022 at 12:03 PM Linus Torvalds
<torvalds@linux-foundation.org> wrote:
>
> Side note: we do need *some* way to do it.

Ooh.

This patch is a work of art.

And I mean that in the worst possible way.

We can do

        typeof(pos) pos

in the 'for ()' loop, and never use __iter at all.

That means that inside the for-loop, we use a _different_ 'pos' than outside.

And then the compiler will not see some "might be uninitialized", but
the outer 'pos' *will* be uninitialized.

Unless, of course, the outer 'pos' had that pointless explicit initializer.

Here - can somebody poke holes in this "work of art" patch?

                     Linus

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