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Date: Sun, 15 Jun 1997 14:33:39 +0200
From: Tommy Hallgren <md6tommy@mdstud.chalmers.se>
Organization: FreeBSD
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To: "Serge A. Babkin" <babkin@hq.icb.chel.su>
CC: hackers@freebsd.org
Subject: Re: C optimizer bug ?
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Hi Serge!

Sometimes when you turn on optimizations, the compiler decides to cache
some data into registers. Loops like

	while(!flag) {}

will be

		mov eax, flag
	label:	tst eax
		branch label

instead of

	label:	mov eax, flag
		tst eax
		branch label

Use the keyword "volatile" to force the loading the contents every time.
Maybe this could be your problem?

Mvh: Tommy(md6tommy@mdstud.chalmers.se)