Goal:
    X1' : list A.t  X1 : list A.t  X : lt_ X1' X1
  ============================
   (let H := CoreTactics.block in
    forall x : t,
    {| pr1 := x; pr2 := x |} = {| pr1 := X1'; pr2 := X1 |} ->
    let H0 := CoreTactics.block in let H1 := CoreTactics.block in False)


DEBUG:Going to execute:
DepElim.introduce p
Level 2: evaluation returns
DepElim.introduce p; DepElim.elim_ind p || induction p
where
p := X
of type
constr of type tacvalue

Level 1: evaluation returns
DepElim.introduce p; DepElim.elim_ind p || induction p
where
p := X
of type
constr of type tacvalue