Goal:
    G : t  z : Z  le : z <= 0
  ============================
   (Some z = Some z /\ z <= 0)


DEBUG:Going to execute:
fun => <coq-core.plugins.ltac::split@0>

Goals:
    G : t  z : Z  le : z <= 0
  ============================
   (Some z = Some z)

    G : t  z : Z  le : z <= 0
  ============================
   (z <= 0)


DEBUG:Going to execute:
<Coq.Init.Tauto.not_dep_intros>

Goals:
    G : t  z : Z  le : z <= 0
  ============================
   (Some z = Some z)

    G : t  z : Z  le : z <= 0
  ============================
   (z <= 0)


DEBUG:Going to execute:
repeat
            match goal with
            | |- ?X1 -> ?X2 => intro
            | |- ~ _ => unfold not at 1; intro
            end