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Date: Fri, 19 Jan 1996 21:06:16 +1100
From: Bruce Evans <bde@zeta.org.au>
Message-Id: <199601191006.VAA32089@godzilla.zeta.org.au>
To: freebsd-hackers@FreeBSD.org, mpp@mpp.minn.net
Subject: Re: kern/subr_diskslice debug messages
Sender: owner-hackers@FreeBSD.org
Precedence: bulk

>I've noticed that if I shutdown into single user mode and
>unmount all my disks, and then do something to access my second
>SCSI hard disk (e.g. fsck it), I will get debug output from 
>sys/kern/subr_diskslice.c.  These are messages generated by the TRACE 
>macro defined in that module.  These messages are only printed if ds_debug 
>is set, which it should not be, and I can't find anything that does
>set it.  One odd this is that ds_debug is declared as volatile.
>Anyone else seen this, or have any clue why these messages are coming out?

It's volatile just to stop gcc deleting it.  Nothing in the kernel should
set it.  Look for array overruns etc.

Bruce