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From: Andy Shevchenko <andy.shevchenko@gmail.com>
Date: Sat, 2 Mar 2024 03:17:32 +0200
To: Kees Cook <keescook@chromium.org>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>,
	"Gustavo A . R . Silva" <gustavoars@kernel.org>,
	Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>,
	Jani Nikula <jani.nikula@linux.intel.com>,
	David Laight <David.Laight@aculab.com>,
	Nick Desaulniers <ndesaulniers@google.com>,
	Martin Uecker <Martin.Uecker@med.uni-goettingen.de>,
	Jonathan Corbet <corbet@lwn.net>, linux-doc@vger.kernel.org,
	Miguel Ojeda <ojeda@kernel.org>, linux-kernel@vger.kernel.org,
	linux-hardening@vger.kernel.org
Subject: Re: [PATCH] compiler.h: Explain how __is_constexpr() works
Message-ID: <ZeJ-LAkSxwBlr9_v@surfacebook.localdomain>
References: <20240301044428.work.411-kees@kernel.org>
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In-Reply-To: <20240301044428.work.411-kees@kernel.org>

Thu, Feb 29, 2024 at 08:44:37PM -0800, Kees Cook kirjoitti:
> The __is_constexpr() macro is dark magic. Shed some light on it with
> a comment to explain how and why it works.

I was under impression that somebody did it already once and it fell through
cracks when has been moved (?) to compiler.h.

Ah, now I see it, https://lore.kernel.org/all/YKeghxRY4FeOKuwb@smile.fi.intel.com/.
It was asked, but till now never fulfilled (maybe Reported-by:/Closes: tag?).

And explanation before was given here:
https://stackoverflow.com/questions/49481217/linux-kernels-is-constexpr-macro.

-- 
With Best Regards,
Andy Shevchenko