On Thu, 09 Aug 2007, Jan Danielsson wrote:
> sometimes I have to run the build.sh-script twice (with identical
> command line). First it will fail somewhere, and second time it will
> pass.

Please post the build.sh command line, the first few lines of output from
build.sh (with the summary of variables and settings), and the
first few lines of error messages.

> Also, it understands that it should build my custom kernel, but it
> doesn't understand _how_ to do that.

How are you asking it to do that, and what goes wrong?  Usually,
"build.sh ... tools ... kernel=MYKERNEL" just works.

> Is this any of this of interest to anyone?

Yes.  We'd like to fix it.

>    Is there any danger in booting NetBSD 4 beta off my USB memory stick,
> and have to init.root chroot to my 3.1 system on my hard drive?

This has more or less the same dangers as running a 3.1 userland with a
netbsd-4 kernel without any encrypted disks or init.root tricks.  Almost
everything should work, because new NetBSD kernels usually have good
backward compatibility with old NetBSD userland programs.  Exceptions to
the usual backward compatibility include mismatches between the userland
and kernel versions of ipf(8) (which might affect upgrades from 3.1 to
4.0), and a change in the threading model in NetBSD-4.99.10 (which will
*not* affect upgrades from 3.1 to 4.0).

--apb (Alan Barrett)