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Date: Thu, 18 Dec 2025 13:18:13 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Segher Boessenkool <segher@kernel.crashing.org>
Cc: Marco Elver <elver@google.com>, Ard Biesheuvel <ardb@kernel.org>,
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	Vincenzo Frascino <vincenzo.frascino@arm.com>,
	kasan-dev@googlegroups.com, linux-kernel@vger.kernel.org,
	linux-toolchains@vger.kernel.org
Subject: Re: [PATCH 0/2] Noinstr fixes for K[CA]SAN with GCOV
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In-Reply-To: <aUPsdDY09Jzn3ILf@gate>

On Thu, Dec 18, 2025 at 05:58:44AM -0600, Segher Boessenkool wrote:

> You might have more success getting the stuff backported to some
> distro(s) you care about?  Or get people to use newer compilers more
> quickly of course, "five years" before people have it is pretty
> ridiculous, two years is at the tail end of things already.

There is a difference between having and requiring it :/ Our current
minimum compiler version is gcc-8 or clang-15 (IIRC).

On the bright side, I think we can be more aggressively with compiler
versions for debug builds vs regular builds. Not being able to build a
KASAN/UBSAN/whateverSAN kernel isn't too big of a problem (IMO).