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Date: Sat, 6 Sep 2008 14:10:32 -0700 (PDT)
From: Linus Torvalds <torvalds@linux-foundation.org>
To: Thomas Gleixner <tglx@linutronix.de>
cc: Alok Kataria <akataria@vmware.com>, Alan Cox <alan@lxorguk.ukuu.org.uk>,
       LKML <linux-kernel@vger.kernel.org>,
       Arjan van de Veen <arjan@infradead.org>,
       "H. Peter Anvin" <hpa@zytor.com>,
       Peter Zijlstra <a.p.zijlstra@chello.nl>, Dan Hecht <dhecht@vmware.com>,
       Garrett Smith <garrett@vmware.com>
Subject: Re: [RFC patch 0/4] TSC calibration improvements
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On Sat, 6 Sep 2008, Thomas Gleixner wrote:
>  
> Where is a guarantee, that excpect is not decremented before we break
> out of the loop ? 

Quite the reverse. We have a guarantee that it _is_ decremented.

Adn that guarantee is very much about the C language.

		for (a ; b ; c) {
			..
		}

translates as

		a;
		while (b) {
			..
	continue:
			c;
		}

And this has absolutely _nothing_ to do with any gcc oddity or anything 
else. 

The fact is, the code that Ingo added was totally bogus. The real bug was 
that he did a totally bogus "--expect" in the argument to that last call. 

Because 'c' *will* have been done after the last iteration of the loop.

			Linus