From: Linus Torvalds Date: Mon, 25 Apr 2005 18:50:29 GMT Subject: Re: [PATCH GIT 0.6] make use of register variables & size_t Message-ID: In-Reply-To: <426D33BA.8040604@tiscali.de> 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. In contrast regparm() actually says something very relevant: it says that the function uses a totally different calling convention. Linus