Index: head/share/mk/bsd.dep.mk
===================================================================
--- head/share/mk/bsd.dep.mk
+++ head/share/mk/bsd.dep.mk
@@ -108,7 +108,7 @@
 .for _LSRC in ${SRCS:M*.l:N*/*}
 .for _LC in ${_LSRC:R}.c
 ${_LC}: ${_LSRC}
-	${LEX} ${LFLAGS} -o${.TARGET} ${.ALLSRC}
+	${LEX} ${LFLAGS} ${LFLAGS.${_LSRC}} -o${.TARGET} ${.ALLSRC}
 OBJS_DEPEND_GUESS.${_LC:R}.o+=	${_LC}
 SRCS:=	${SRCS:S/${_LSRC}/${_LC}/}
 CLEANFILES+= ${_LC}
@@ -129,7 +129,7 @@
 ${_YC}: .PHONY .META
 .endif
 ${_YC}: ${_YSRC}
-	${YACC} ${YFLAGS} ${.ALLSRC}
+	${YACC} ${YFLAGS} ${YFLAGS.${_YSRC}} ${.ALLSRC}
 	cp y.tab.c ${_YC}
 CLEANFILES+= y.tab.c y.tab.h
 .elif !empty(YFLAGS:M-d)
@@ -142,13 +142,13 @@
 ${_YC}: .PHONY .META
 .endif
 ${_YC}: ${_YSRC}
-	${YACC} ${YFLAGS} -o ${_YC} ${.ALLSRC}
+	${YACC} ${YFLAGS} ${YFLAGS.${_YSRC}} -o ${_YC} ${.ALLSRC}
 SRCS+=	${_YH}
 CLEANFILES+= ${_YH}
 .endfor
 .else
 ${_YC}: ${_YSRC}
-	${YACC} ${YFLAGS} -o ${_YC} ${.ALLSRC}
+	${YACC} ${YFLAGS} ${YFLAGS.${_YSRC}} -o ${_YC} ${.ALLSRC}
 .endif
 OBJS_DEPEND_GUESS.${_YC:R}.o+=	${_YC}
 .endfor