But this all makes me question the "BUILDLINK_DEPMETHOD.flex?= build"
in devel/flex/buildlink3.mk. Why is that there? I don't understand
that. It seems like that should never be done inside a buildlink3.mk.
It seems like the default should always be "full", and it should be
up to the caller that includes it to set "BUILDLINK_DEPMETHOD.flex?=
build" before including it in order to change that default. Otherwise,
every place a buildlink3.mk is included, the developer has to inspect
the buildlink3.mk to see whether it defaults to a "full" or "build"
BUILDLINK_DEPMETHOD.<pkg>. That seems confusing.