linux-kernel - Re: [RFC PATCH 1/2] bits: introduce ffs

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Message-ID: <alpine.DEB.2.21.2601130131080.12909@angie.orcam.me.uk>
Date: Tue, 13 Jan 2026 01:40:37 +0000 (GMT)
From: "Maciej W. Rozycki" <macro@...am.me.uk>
To: David Laight <david.laight.linux@...il.com>
cc: Thomas Zimmermann <tzimmermann@...e.de>, Petr Tesarik <ptesarik@...e.com>, 
    Yury Norov <yury.norov@...il.com>, 
    Rasmus Villemoes <linux@...musvillemoes.dk>, 
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    Pablo Neira Ayuso <pablo@...filter.org>, Florian Westphal <fw@...len.de>, 
    linux-kernel@...r.kernel.org
Subject: Re: [RFC PATCH 1/2] bits: introduce ffs_val()

On Mon, 12 Jan 2026, David Laight wrote:

> OTOH I'm pretty sure most modern C code assumes two's compliment binary
> numbers (and NULL being the all-zero bit pattern).

 FWIW ISO C23 mandates the two's complement integer sign representation.  
Other sign representations are no longer allowed.

  Maciej