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Date: Fri, 22 Oct 2004 12:30:30 +0200 (CEST)
From: Harti Brandt <harti@freebsd.org>
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Subject: Re: cvs commit: src/sys/sys protosw.h src/sys/kern  
 uipc_domain.cuipc_socket2.c
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On Fri, 22 Oct 2004, [iso-8859-1] Dag-Erling Sm?rgrav wrote:

DS>Harti Brandt <harti@freebsd.org> writes:
DS>> You cannot prevent the compiler from makeing temporary copies.
DS>
DS>Yes, you can, using the volatile keyword.

That doesn't help you if the compiler needs to fetch the function pointer
into a register to call it. That would be allowed even if you declare the
pointer volatile. Something like

	mov	funcptr, r0
	call	@r0

If some other thread slips just between these two statements your call may 
end up somewhere.

harti