http://www.berklix.com/~jhs/src/bsd/fixes/FreeBSD/ports/gen/Mk/bsd.port.mk.configure-recursive.2.REL=12.0-CURRENT.diff

This patch allows a human to get all the configure done, that might
require manual input, then a 2nd make can be run later allowing
human to leave the CPU unattended not neading human input.

*** 12.0-CURRENT-2016-09-01/ports/Mk/bsd.port.mk	Thu Sep  1 19:26:27 2016
--- new-generic/ports/Mk/bsd.port.mk	Thu Sep  1 19:33:08 2016
***************
*** 3347,3352 ****
--- 3347,3363 ----
  .endif
  .endif
  
+ .if !target(configure-recursive)
+ configure-recursive:	configure
+ 	@${ECHO_MSG} "===> ${.CURDIR}"
+ 	@${ECHO_MSG} -n "Deps: " ; ${ECHO_MSG} ${ALL-DEPENDS-LIST}
+ 	@for dir in $$(${ALL-DEPENDS-LIST}); do \
+ 		( cd $$dir; echo -n "For ${.CURDIR}: " ;\
+ 			pwd; ${MAKE} configure ) ; \
+ 	done
+ 	@${ECHO_MSG} "<=== ${.CURDIR}"
+ .endif
+ 
  # Build
  # XXX: ${MAKE_ARGS:N${DESTDIRNAME}=*} would be easier but it is not valid with the old fmake
  DO_MAKE_BUILD?=	${SETENV} ${MAKE_ENV} ${MAKE_CMD} ${MAKE_FLAGS} ${MAKEFILE} ${_MAKE_JOBS} ${MAKE_ARGS:C,^${DESTDIRNAME}=.*,,g}