Goal:
    z : Z  z0 : Z  H0 : False
  ============================
   (z0 <= z)%Z


DEBUG:Going to execute:
elim H
Level 3: evaluation returns
<coq-core.plugins.tauto::is_empty@0>
where
tauto_flags := 
of type
tauto_flags
X1 := False
of type
constr of type tacvalue