verify: a.I: check: deadlock: ok
verify: a.I: check: unreachable: ok
verify: a.I: check: livelock: ok
verify: a.I: check: deterministic: ok
verify: b.I: check: deadlock: ok
verify: b.I: check: unreachable: ok
verify: b.I: check: livelock: ok
verify: b.I: check: deterministic: ok
