Make variables to force non default libraries and includes?

[Warner Losh]

On Apr 28, 2014, at 1:48 AM, Julian Elischer <julian at FreeBSD.org> wrote:

> I need to do the equivalent of  "cd /usr/src/cddl/usr.sbin/dtrace; make DESTDIR=/mumble all install”

cd /usr/src
make distributeworld DESTDIR=/mumble
cd cddl/usr.sbin/dtrace
make buildenv
make all install

> but it pulls in libraries from the base system, which differ slightly from those in the source tree.

The above will create the right /mumble hierarchy, and will pull the libraries from the build rather than the local system.

> How can I force it to use /mumble2/include and /mumble2/lib instead of / ?
> 
> I can pre-populate /mumble2 using "make buildworld", "make libraries", and "make includes" but
> I need to be able to do selective builds of just subdirectories after that..  I haven't spotted the right way of forcing the use of the "--system_root /mumble2" option in the compiles.
> 
> I know we do it in 'buildworld' is there a more generic way?
> 
> I have been looking in the .mk files but I haven't spotted it so far.

You’re asking for some serious split-brain action. chroot builds are likely your best option. There’s no easy way to force this, although you might get some milage out of WMAKEENV options, but I think we bake most of the where to look for things options into the binaries. One crazy option would be to set CC=“cc —sysroot /mumble” but I’m sure there be dragons there…

Good luck with this crazy, never have we supported it very well, option :)

Warner