From: Randy Dunlap <rdunlap@infradead.org>
To: Ahmed Soliman <ahmedsoliman0x666@gmail.com>,
linux-kernel@vger.kernel.org
Subject: Re: how does 0x##p##q work
Date: Fri, 24 Jul 2015 09:58:18 -0700 [thread overview]
Message-ID: <55B26EAA.70209@infradead.org> (raw)
In-Reply-To: <CAAGnT3YNz+QYaSRPV6Led+HL0rUeva=QwqbVgVSm1tLAFxD0rg@mail.gmail.com>
On 07/24/15 09:02, Ahmed Soliman wrote:
> I was working on cleaning up some files in the crypto dirctory using
> checkpatch.pl
> and I found this strange define in crypto/gf128mul.c
> #define xx(p, q) 0x##p##q
> It just seems really weird macro and I cant figure out what is it
> supposed to do!!
## is defined in any complete C language spec (it's a preprocessor directive).
It is used for string concatenation, aka pasting or gluing strings together.
google can find lots of references for it if you need more info.
--
~Randy
prev parent reply other threads:[~2015-07-24 16:58 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-07-24 16:02 how does 0x##p##q work Ahmed Soliman
2015-07-24 16:58 ` Randy Dunlap [this message]
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