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From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Sun, 25 Feb 2024 09:13:56 -0800
Message-ID: <CAHk-=wgNh5Gw7RTuaRe7mvf3WrSGDRKzdA55KKdTzKt3xPCnLg@mail.gmail.com>
Subject: Re: [PATCH next v2 08/11] minmax: Add min_const() and max_const()
To: David Laight <David.Laight@aculab.com>
Cc: "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>, Netdev <netdev@vger.kernel.org>, 
	"dri-devel@lists.freedesktop.org" <dri-devel@lists.freedesktop.org>, Jens Axboe <axboe@kernel.dk>, 
	"Matthew Wilcox (Oracle)" <willy@infradead.org>, Christoph Hellwig <hch@infradead.org>, 
	"linux-btrfs@vger.kernel.org" <linux-btrfs@vger.kernel.org>, Andrew Morton <akpm@linux-foundation.org>, 
	Andy Shevchenko <andriy.shevchenko@linux.intel.com>, 
	"David S . Miller" <davem@davemloft.net>, Dan Carpenter <dan.carpenter@linaro.org>, 
	Jani Nikula <jani.nikula@linux.intel.com>
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On Sun, 25 Feb 2024 at 08:53, David Laight <David.Laight@aculab.com> wrote:
>
> The expansions of min() and max() contain statement expressions so are
> not valid for static intialisers.
> min_const() and max_const() are expressions so can be used for static
> initialisers.

I hate the name.

Naming shouldn't be about an implementation detail, particularly not
an esoteric one like the "C constant expression" rule. That can be
useful for some internal helper functions or macros, but not for
something that random people are supposed to USE.

Telling some random developer that inside an array size declaration or
a static initializer you need to use "max_const()" because it needs to
syntactically be a constant expression, and our regular "max()"
function isn't that, is just *horrid*.

No, please just use the traditional C model of just using ALL CAPS for
macro names that don't act like a function.

Yes, yes, that may end up requiring getting rid of some current users of

  #define MIN(a,b) ((a)<(b) ? (a):(b))

but dammit, we don't actually have _that_ many of them, and why should
we have random drivers doing that anyway?

              Linus