Goal:
  
  A : Type
  R : ReflectEq A
  x : A
  y : A
  Heq_anonymous : false = (x == y)
  H : x = y
  ============================
   False


DEBUG:Going to execute:
match H with
           | H' => fail 2
           | _ => unify X Y; clear H' || clear H
           end
Level 4: Backtrace:

x is used in hypothesis Heq_anonymous.
Level 4: Backtrace:

x is used in hypothesis Heq_anonymous.
Level 4: Backtrace:

x is used in hypothesis Heq_anonymous.
Level 4: Backtrace:

x is used in hypothesis Heq_anonymous.
Level 4: Backtrace:

x is used in hypothesis Heq_anonymous.
Level 4: Backtrace:

x is used in hypothesis Heq_anonymous.
Level 4: Backtrace:

x is used in hypothesis Heq_anonymous.
Level 3: Backtrace:

x is used in hypothesis Heq_anonymous.