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Date: Tue, 26 Aug 2025 09:56:06 -0700
From: Kees Cook <kees@kernel.org>
To: Rasmus Villemoes <ravi@prevas.dk>
Cc: Yury Norov <yury.norov@gmail.com>, kernel test robot <lkp@intel.com>,
	Vineet Gupta <vgupta@kernel.org>,
	linux-snps-arc@lists.infradead.org, linux-kernel@vger.kernel.org,
	linux-hardening@vger.kernel.org
Subject: Re: [PATCH] arc: Fix __fls() const-foldability via __builtin_clzl()
Message-ID: <202508260955.2DE50A3FB@keescook>
References: <20250826034354.work.684-kees@kernel.org>
 <87ldn644d0.fsf@prevas.dk>
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In-Reply-To: <87ldn644d0.fsf@prevas.dk>

On Tue, Aug 26, 2025 at 03:08:59PM +0200, Rasmus Villemoes wrote:
> If __builtin_arc_fls() simply doesn't qualify for attr_const for
> $reason, I think it would be good to have that documented in the commit
> msg. If it does, I think a gcc ticket and link to that would be in order.

I already sent the patch to fix it. :)

https://gcc.gnu.org/pipermail/gcc-patches/2025-August/693273.html

-- 
Kees Cook