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Date: Sun, 17 Dec 1995 06:17:04 +1100
From: Bruce Evans <bde@zeta.org.au>
Message-Id: <199512161917.GAA07610@godzilla.zeta.org.au>
To: CVS-committers@freefall.freebsd.org, cvs-sys@freefall.freebsd.org,
        peter@freefall.freebsd.org
Subject: Re: cvs commit: src/sys/i386/i386 autoconf.c machdep.c
Sender: owner-commit@FreeBSD.ORG
Precedence: bulk

>  Modified:    sys/i386/i386  autoconf.c machdep.c
>  Log:
>  Catch a couple more null devsw dereferences...

There should be dummy tables so that all these tests aren't necessary:

	initial bdevsw[] = { &dummy, &dummy, ... };

Similarly, inside each *bdevsw[maj], there should be pointers to dummy
functions, not null pointers.

The cost of indirect tables may be more than compensated for by the
simpler indexing:

	old				now
	---				---
	(&bdevsw[maj])->d_open		*bdevsw[maj]->d_open
	^^^^^^^^^^^^^^			^^^^^^^^^^^^
	complicated address calc.	simple address calc., extra indirection

Bruce