In article <m19DTFk-000B3kC@proven.weird.com> you write:
>Why not do "make includes" before "make do-tools" for build.sh?

In the general case, because "make includes" needs ${INSTALL}, which is
built by "make do-tools".

>It's necessary if you are trying to get buy with using "build.sh -u"
>_and_ if changes to headers are needed in order to successfully build
>some tools,

NetBSD _should_ be able to compile on earlier versions of itself (at least
back to the latest formal release), so unless your host system is
comprehensively screwed, this situation should never arise.  I don't think
that requiring some effort to recover a screwed host system is unreasonable.

-- 
Ben Harris                                                   <bjh21@netbsd.org>
Portmaster, NetBSD/acorn26           <URL:http://www.netbsd.org/Ports/acorn26/>