From: Arjan van de Ven <arjan@infradead.org>
Date: Mon, 25 Apr 2005 20:50:09 GMT
Subject: Re: [PATCH GIT 0.6] make use of register variables & size_t
Message-ID: <1114462210.8442.54.camel@laptopd505.fenrus.org>
In-Reply-To: <Pine.LNX.4.58.0504251147290.18901@ppc970.osdl.org>

On Mon, 2005-04-25 at 11:50 -0700, Linus Torvalds wrote:
> 
> On Mon, 25 Apr 2005, Matthias-Christian Ott wrote:
> >
> > But this makes, like "register", direct use of processor registers (it
> > stores int arguments in eax, ebx, etc.).
> 
> No. It make _unlike_ "register", direct use of processor registers.
> 
> The "register" keyword does _not_ use processor registers. It's just 
> syntactic fluff, and tells the compiler exactly one thing:
> 
>  - that the compiler should warn if you take the address of such a thing.
> 
> In addition, the compiler may generate code that takes it into account, 
> which most likely means _worse_ code than if it didn't take it into 
> account.

afaik gcc just otherwise ignores it entirely.