Goal:
  
  A : Type
  P : list A → list A → A → A → Type
  a : A
  Γ : list A
  d' : A
  Γ'0 : list A
  Hrel : All2_fold P Γ Γ'0
  p : P Γ Γ'0 a d'
  ============================
   (Some d' = Some ?d' × All2_fold P Γ Γ'0 × P Γ Γ'0 a ?d')


DEBUG:Going to execute:
Ltac.split
Level 2: evaluation returns
<coq-core.plugins.tauto::is_conj@0>
where
tauto_flags := 
of type
tauto_flags
X1 := Some d' = Some ?d' × All2_fold P Γ Γ'0 × P Γ Γ'0 a ?d'
of type
constr of type tacvalue