Re: [PATCH 6/8] i386: bitops: Don't mark memory as clobbered unnecessarily

[Linus Torvalds <torvalds@linux-foundation.org>]

On Tue, 24 Jul 2007, Jeremy Fitzhardinge wrote:
> >
> > But gcc docs also talk about the other things volatile means, including 
> > "not significantly moved".
> 
> Actually, it doesn't.  In fact it goes out of its way to say that "asm
> volatile" statements can be moved quite a bit, with respect to other
> asms, other code, jumps, basic blocks, etc.

Ahh. That's newer.

Historically, gcc manuals used to say "may not be deleted or significantly 
reordered".

So they've weakened what it means, probably exactly because it wasn't 
well-defined before either.

		Linus
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