linux-kernel - Re: [PATCH 2/6] treewide: remove using list iterator after loop body as a ptr

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Date:   Mon, 28 Feb 2022 16:45:11 -0800
From:   Linus Torvalds <torvalds@...ux-foundation.org>
To:     Matthew Wilcox <willy@...radead.org>
Cc:     Christian König <christian.koenig@....com>,
        Jakob Koschel <jakobkoschel@...il.com>,
        alsa-devel@...a-project.org, linux-aspeed@...ts.ozlabs.org,
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Subject: Re: [PATCH 2/6] treewide: remove using list iterator after loop body
 as a ptr

On Mon, Feb 28, 2022 at 3:26 PM Matthew Wilcox <willy@...radead.org> wrote:
>
> #define ___PASTE(a, b)  a##b
> #define __PASTE(a, b) ___PASTE(a, b)
> #define _min(a, b, u) ({         \

Yeah, except that's ugly beyond belief, plus it's literally not what
we do in the kernel.

Really. The "-Wshadow doesn't work on the kernel" is not some new
issue, because you have to do completely insane things to the source
code to enable it.

Just compare your uglier-than-sin version to my straightforward one.
One does the usual and obvious "use a private variable to avoid the
classic multi-use of a macro argument". And the other one is an
abomination.

              Linus