Subject: Re: building for multiple archs from a read-only tree
To: Rob Healey <>
From: David Querbach <>
List: current-users
Date: 12/22/2000 09:52:43
> >     So, is there some way to convince the make process to put ALL files
> >     somewhere else WITHOUT using symlinks in the source tree? ALL files
> >     includes droppings like .depend in addition to .o's, .so's, .a's and
> >     such.
> I think this is what the BSDOBJDIR stuff is for. I did not used it yet
> tho, so I can't tell you what the exact steps are. Chances are there
> is description on NetBSD FAQ.

For cross-compiling, I use the following:

	export BASEDIR=<whatever>

	export BSDSRCDIR=${BASEDIR}/src
        export BSDOBJDIR=${BASEDIR}/obj
        export KERNOBJDIR=${BSDOBJDIR}.${MACHINE}/sys/arch/${MACHINE}

        export OBJMACHINE=yes
        export USR_OBJMACHINE=yes

This gives an object tree named `obj.$MACHINE' with each directory pointed
to by a symlink in the source tree.  Each symlink is also named
`obj.$MACHINE', which allows building for multiple targets from the same
source tree.  The KERNOBJDIR line moves the kernel build over into the
object tree as well.

Since I'm cross-compiling, I don't want the results dumped in the root, so
the DESTDIR symbol specifies where to build the target system
(`dst.$MACHINE') and the RELEASEDIR symbol specifies where to put the
tarballs (`rel.$MACHINE').

As far as I can tell, the only way to have a fully read-only source tree is
with a union mount.


David Querbach
Real-Time Systems Inc.