Use of COMPAT Kernel Options

[Gardner Bell]

--- On Fri, 12/4/09, Roland Smith <rsmith at xs4all.nl> wrote:

> From: Roland Smith <rsmith at xs4all.nl>
> Subject: Re: Use of COMPAT Kernel Options
> To: "APseudoUtopia" <apseudoutopia at gmail.com>
> Cc: "FreeBSD Questions" <freebsd-questions at freebsd.org>
> Date: Friday, December 4, 2009, 9:52 PM
> On Fri, Dec 04, 2009 at 04:39:59PM
> -0500, APseudoUtopia wrote:
> > Hello,
> > 
> > I'm working on editing the kernel configuration file
> for a custom
> > kernel. The system will be running FreeBSD
> 8.0-RELEASE-p1. I'm
> > wondering about the use of the COMPAT options in the
> kernel config.
> > COMPAT_43
> 
> Well, COMPAT_43 one isn't even in GENERIC anymore, so I
> guess it is not that
> important anymore.
> 
> > COMPAT_43TTY
> 
> This is still in the GENERIC kernel. I'd keep it in
> initially. Then build a
> kernel without it. If that fails to start the system
> properly, you'll always
> have a good kernel to fall back on.
> 
> Have a look at what is written under COMPATIBILITY OPTIONS
> in /sys/conf/NOTES.
> 
> > COMPAT_FREEBSD[4-7]
> 
> If you do not have binaries from ealier FreeBSD versions
> around, you can skip
> these. 
> 

FWIW, a FreeBSD 8.0 kernel fails to build without COMPAT_FREEBSD7 so I'd keep that.