Re: how does 0x##p##q work

[Randy Dunlap]

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
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