Re: macro _set_base - "do - while(0)" question

From: DervishD
Date: Wed Jan 02 2008 - 08:01:17 EST


Hi Abdel :)

* Abdel <draconux@xxxxxxxxx> dixit:
> In file include/asm-i386/system.h, _set_base and _set_limit use an
> useless do ... while(0)
>
> Why is this needed ?

Google for "do while swallow semicolon". This looks like an useless and
weird construction but it is very useful when it comes to macros (you
can define variables inside the block and you can use your macro as any
other statement, it won't swallow the semicolon).

RaÃl NÃÃez de Arenas Coronado
--
Linux Registered User 88736 | http://www.dervishd.net
It's my PC and I'll cry if I want to... RAmen!
We are waiting for 13 Feb 2009 23:31:30 +0000 ...
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