IMHO, the only sane way to do this is to write builtin.mk support for
every package of concern; joerg@ convinced me of this back in 2006
when the modularization was just beginning. ;)

Any apparent "short-cut" will ultimately demand more effort fixing it
down the road when problems surface.  Moreover, there are subtler
issues than "does it work with configuration C on platform P" to
contend with.  I've noticed that there are often subtle API/ABI
changes which may or may not cause any apparent issues--until you
encounter the "right" situation, e.g. the last two versions of
renderproto and libXxf86dga with server branches 1.3 v. 1.4.  More
applications these days are using pkg-config to sanity check things
like API versions, and given the myriad platforms we strive to
support, I can't imagine "faking" this.

--Blair