Goal:
  
  G : t
  HI : invariants G
  HG : acyclic_no_loop G
  s0 : VSet.t
  x : V.t
  y : V.t
  d : DisjointAdd x s0 (V G)
  e : EdgeOf G x y
  p : SPath G s0 y (s G)
  IHp : let H := CoreTactics.block in
        forall (x : V.t) (z : Z) (p0 : SPath G (V G) x (s G)),
        {|
          pr1 := {| pr1 := V G; pr2 := {| pr1 := x; pr2 := s G |} |};
          pr2 := p0
        |} =
        {|
          pr1 := {| pr1 := s0; pr2 := {| pr1 := y; pr2 := s G |} |}; pr2 := p
        |} ->
        let H0 := CoreTactics.block in
        sweight p0 = z ->
        ~ VSet.In x (V G) -> let H1 := CoreTactics.block in z = 0
  z0 : Z
  ============================
   (let H := CoreTactics.block in
    sweight (spath_step G s0 (V G) x y (s G) d e p) = z0 ->
    ~ VSet.In x (V G) -> let H0 := CoreTactics.block in z0 = 0)


DEBUG:Going to execute:
cbn beta in hyp; eqns_specialize_eqs_block hyp;
            cbn[eq_rect_r eq_rect] in hyp
Level 1: Backtrace:

Tactic failure: Nothing to do in hypothesis IHp(forall 
                                                 (x : V.t) 
                                                 (z : Z)
                                                 (p0 : SPath G (V G) x (s G)),
                                                {|
                                                 pr1 :=
                                                 {|
                                                 pr1 := V G;
                                                 pr2 :=
                                                 {| pr1 := x; pr2 := s G |}
                                                 |};
                                                 pr2 := p0
                                                |} =
                                                {|
                                                 pr1 :=
                                                 {|
                                                 pr1 := s0;
                                                 pr2 :=
                                                 {| pr1 := y; pr2 := s G |}
                                                 |};
                                                 pr2 := p
                                                |} ->
                                                let H := CoreTactics.block in
                                                sweight p0 = z ->
                                                ~ VSet.In x (V G) ->
                                                let H0 := CoreTactics.block
                                                 in
                                                z = 0).
Level 1: Backtrace:

Tactic failure: Nothing to do in hypothesis IHp(forall 
                                                 (x : V.t) 
                                                 (z : Z)
                                                 (p0 : SPath G (V G) x (s G)),
                                                {|
                                                 pr1 :=
                                                 {|
                                                 pr1 := V G;
                                                 pr2 :=
                                                 {| pr1 := x; pr2 := s G |}
                                                 |};
                                                 pr2 := p0
                                                |} =
                                                {|
                                                 pr1 :=
                                                 {|
                                                 pr1 := s0;
                                                 pr2 :=
                                                 {| pr1 := y; pr2 := s G |}
                                                 |};
                                                 pr2 := p
                                                |} ->
                                                let H := CoreTactics.block in
                                                sweight p0 = z ->
                                                ~ VSet.In x (V G) ->
                                                let H0 := CoreTactics.block
                                                 in
                                                z = 0).
Level 1: Backtrace:

Tactic failure: Nothing to do in hypothesis IHp(forall 
                                                 (x : V.t) 
                                                 (z : Z)
                                                 (p0 : SPath G (V G) x (s G)),
                                                {|
                                                 pr1 :=
                                                 {|
                                                 pr1 := V G;
                                                 pr2 :=
                                                 {| pr1 := x; pr2 := s G |}
                                                 |};
                                                 pr2 := p0
                                                |} =
                                                {|
                                                 pr1 :=
                                                 {|
                                                 pr1 := s0;
                                                 pr2 :=
                                                 {| pr1 := y; pr2 := s G |}
                                                 |};
                                                 pr2 := p
                                                |} ->
                                                let H := CoreTactics.block in
                                                sweight p0 = z ->
                                                ~ VSet.In x (V G) ->
                                                let H0 := CoreTactics.block
                                                 in
                                                z = 0).
Level 1: Backtrace:

Tactic failure: Nothing to do in hypothesis IHp(forall 
                                                 (x : V.t) 
                                                 (z : Z)
                                                 (p0 : SPath G (V G) x (s G)),
                                                {|
                                                 pr1 :=
                                                 {|
                                                 pr1 := V G;
                                                 pr2 :=
                                                 {| pr1 := x; pr2 := s G |}
                                                 |};
                                                 pr2 := p0
                                                |} =
                                                {|
                                                 pr1 :=
                                                 {|
                                                 pr1 := s0;
                                                 pr2 :=
                                                 {| pr1 := y; pr2 := s G |}
                                                 |};
                                                 pr2 := p
                                                |} ->
                                                let H := CoreTactics.block in
                                                sweight p0 = z ->
                                                ~ VSet.In x (V G) ->
                                                let H0 := CoreTactics.block
                                                 in
                                                z = 0).
Level 1: Backtrace:

Tactic failure: Nothing to do in hypothesis IHp(forall 
                                                 (x : V.t) 
                                                 (z : Z)
                                                 (p0 : SPath G (V G) x (s G)),
                                                {|
                                                 pr1 :=
                                                 {|
                                                 pr1 := V G;
                                                 pr2 :=
                                                 {| pr1 := x; pr2 := s G |}
                                                 |};
                                                 pr2 := p0
                                                |} =
                                                {|
                                                 pr1 :=
                                                 {|
                                                 pr1 := s0;
                                                 pr2 :=
                                                 {| pr1 := y; pr2 := s G |}
                                                 |};
                                                 pr2 := p
                                                |} ->
                                                let H := CoreTactics.block in
                                                sweight p0 = z ->
                                                ~ VSet.In x (V G) ->
                                                let H0 := CoreTactics.block
                                                 in
                                                z = 0).