_icomps
(l)->_icomps.c1 = (l)->_icomps.c2 = (l)->_icomps.c3 = \
(l)->_icomps.c4 = (l)->_icomps.c5 = (l)->_icomps.c6 = \
(l)->_icomps.c7 = (l)->_icomps.c8 = EMPTY_SET, \