DV_FIRST_ENTRY
for (dv = DV_FIRST_ENTRY(ddv); dv; dv = next) {
for (dv = DV_FIRST_ENTRY(ddv); dv; dv = DV_NEXT_ENTRY(ddv, dv)) {
for (dv = DV_FIRST_ENTRY(ddv); dv; dv = DV_NEXT_ENTRY(ddv, dv)) {
ASSERT(DV_FIRST_ENTRY(dv) == NULL);
for (dv = DV_FIRST_ENTRY(ddv); dv;