linux-kernel - Re: [PATCH 02/10] compiler.h: add is_const() as a replacement of __is

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <b3bd6d4ef485dbb5db4c784f4e42f76adce502dc.camel@gwdg.de>
Date: Sat, 7 Dec 2024 16:10:31 +0100
From: Martin Uecker <muecker@...g.de>
To: Vincent Mailhol <vincent.mailhol@...il.com>
CC: David Laight <David.Laight@...lab.com>, Linus Torvalds
	<torvalds@...ux-foundation.org>, Luc Van Oostenryck
	<luc.vanoostenryck@...il.com>, Nathan Chancellor <nathan@...nel.org>, "Nick
 Desaulniers" <ndesaulniers@...gle.com>, Bill Wendling <morbo@...gle.com>,
	Justin Stitt <justinstitt@...gle.com>, Yury Norov <yury.norov@...il.com>,
	Rasmus Villemoes <linux@...musvillemoes.dk>, Kees Cook <kees@...nel.org>,
	"Gustavo A. R. Silva" <gustavoars@...nel.org>, Jani Nikula
	<jani.nikula@...ux.intel.com>, Joonas Lahtinen
	<joonas.lahtinen@...ux.intel.com>, Rodrigo Vivi <rodrigo.vivi@...el.com>,
	Tvrtko Ursulin <tursulin@...ulin.net>, David Airlie <airlied@...il.com>,
	Simona Vetter <simona@...ll.ch>, Suzuki K Poulose <suzuki.poulose@....com>,
	Mike Leach <mike.leach@...aro.org>, James Clark <james.clark@...aro.org>,
	Alexander Shishkin <alexander.shishkin@...ux.intel.com>, Rikard Falkeborn
	<rikard.falkeborn@...il.com>, "linux-sparse@...r.kernel.org"
	<linux-sparse@...r.kernel.org>, "linux-kernel@...r.kernel.org"
	<linux-kernel@...r.kernel.org>, "llvm@...ts.linux.dev"
	<llvm@...ts.linux.dev>, "linux-hardening@...r.kernel.org"
	<linux-hardening@...r.kernel.org>, "intel-gfx@...ts.freedesktop.org"
	<intel-gfx@...ts.freedesktop.org>, "dri-devel@...ts.freedesktop.org"
	<dri-devel@...ts.freedesktop.org>, "coresight@...ts.linaro.org"
	<coresight@...ts.linaro.org>, "linux-arm-kernel@...ts.infradead.org"
	<linux-arm-kernel@...ts.infradead.org>
Subject: Re: [PATCH 02/10] compiler.h: add is_const() as a replacement of
 __is_constexpr()

Am Samstag, dem 07.12.2024 um 22:50 +0900 schrieb Vincent Mailhol:
> On Sat. 7 Dec. 2024 à 22:19, Martin Uecker <muecker@...g.de> wrote:
> > 
...

> 
> I was invited to WG14 this September. For now, I am only lurking. The
> thing I have in mind right now is to write a paper to allow the use of
> static_assert() in expressions (i.e. make it return 0 on success).
> That should be a relatively small change, but would bring a nice
> quality of life improvement.
> 
> For context, look at this:
> 
>   https://lore.kernel.org/all/CAHk-=wjLSEcZ5LdW+3C+9rtjvNPHZT6zdk0POj67T5k2ZpDbgA@mail.gmail.com/T/#m1ba33a804b4041154b72a1d0333f90ec7204c461

What one can do is put it into a structure.

#define const_assert(x) \
    (sizeof(struct { _Static_assert(x, ""); }))

but yeah, also a hack to work around a limitation of the standard
feature.

Martin