diff --git a/bench/stutter/stutter_invariance_formulas.cc b/bench/stutter/stutter_invariance_formulas.cc
index 9ed9effe2..826185d23 100644
--- a/bench/stutter/stutter_invariance_formulas.cc
+++ b/bench/stutter/stutter_invariance_formulas.cc
@@ -1,5 +1,5 @@
 // -*- coding: utf-8 -*-
-// Copyright (C) 2014, 2015 Laboratoire de Recherche et
+// Copyright (C) 2014, 2015, 2016 Laboratoire de Recherche et
 // Développement de l'Epita (LRDE).
 //
 // This file is part of Spot, a model checking library.
@@ -40,7 +40,7 @@ const struct argp_child children[] =
 
 namespace
 {
-  class stut_processor: public job_processor
+  class stut_processor final: public job_processor
   {
   public:
     spot::translator& trans;
diff --git a/bin/autfilt.cc b/bin/autfilt.cc
index 53d642731..e0155a4e7 100644
--- a/bin/autfilt.cc
+++ b/bin/autfilt.cc
@@ -601,7 +601,7 @@ parse_opt(int key, char* arg, struct argp_state*)
 
 namespace
 {
-  class hoa_processor: public job_processor
+  class hoa_processor final: public job_processor
   {
   private:
     spot::postprocessor& post;
diff --git a/bin/common_output.cc b/bin/common_output.cc
index 54cf2badf..74d8ea8a1 100644
--- a/bin/common_output.cc
+++ b/bin/common_output.cc
@@ -153,7 +153,7 @@ namespace
     const char* suffix;
   };
 
-  class printable_formula:
+  class printable_formula final:
     public spot::printable_value<const formula_with_location*>
   {
   public:
@@ -171,7 +171,7 @@ namespace
     }
   };
 
-  class formula_printer: protected spot::formater
+  class formula_printer final: protected spot::formater
   {
   public:
     formula_printer(std::ostream& os, const char* format)
diff --git a/bin/dstar2tgba.cc b/bin/dstar2tgba.cc
index 4ce7c8031..97f59be07 100644
--- a/bin/dstar2tgba.cc
+++ b/bin/dstar2tgba.cc
@@ -1,5 +1,5 @@
 // -*- coding: utf-8 -*-
-// Copyright (C) 2013, 2014, 2015 Laboratoire de Recherche et
+// Copyright (C) 2013, 2014, 2015, 2016 Laboratoire de Recherche et
 // Développement de l'Epita (LRDE).
 //
 // This file is part of Spot, a model checking library.
@@ -106,7 +106,7 @@ parse_opt(int key, char* arg, struct argp_state*)
 
 namespace
 {
-  class dstar_processor: public job_processor
+  class dstar_processor final: public job_processor
   {
   public:
     spot::postprocessor& post;
diff --git a/bin/ltl2tgba.cc b/bin/ltl2tgba.cc
index 4a323c5d4..94e69ac80 100644
--- a/bin/ltl2tgba.cc
+++ b/bin/ltl2tgba.cc
@@ -109,7 +109,7 @@ parse_opt(int key, char* arg, struct argp_state*)
 
 namespace
 {
-  class trans_processor: public job_processor
+  class trans_processor final: public job_processor
   {
   public:
     spot::translator& trans;
diff --git a/bin/ltl2tgta.cc b/bin/ltl2tgta.cc
index 5bbe47e70..045c342ea 100644
--- a/bin/ltl2tgta.cc
+++ b/bin/ltl2tgta.cc
@@ -1,6 +1,6 @@
 // -*- coding: utf-8 -*-
-// Copyright (C) 2012, 2013, 2014, 2015 Laboratoire de Recherche et
-// Développement de l'Epita (LRDE).
+// Copyright (C) 2012, 2013, 2014, 2015, 2016 Laboratoire de Recherche
+// et Développement de l'Epita (LRDE).
 //
 // This file is part of Spot, a model checking library.
 //
@@ -159,7 +159,7 @@ parse_opt(int key, char* arg, struct argp_state*)
 
 namespace
 {
-  class trans_processor: public job_processor
+  class trans_processor final: public job_processor
   {
   public:
     spot::translator& trans;
diff --git a/bin/ltlcross.cc b/bin/ltlcross.cc
index b2f8942a2..04f908dd3 100644
--- a/bin/ltlcross.cc
+++ b/bin/ltlcross.cc
@@ -485,7 +485,7 @@ parse_opt(int key, char* arg, struct argp_state*)
 
 namespace
 {
-  class xtranslator_runner: public translator_runner
+  class xtranslator_runner final: public translator_runner
   {
   public:
     xtranslator_runner(spot::bdd_dict_ptr dict)
@@ -821,7 +821,7 @@ namespace
   typedef
   std::unordered_set<spot::formula> fset_t;
 
-  class processor: public job_processor
+  class processor final: public job_processor
   {
     spot::bdd_dict_ptr dict = spot::make_bdd_dict();
     xtranslator_runner runner;
diff --git a/bin/ltldo.cc b/bin/ltldo.cc
index 1434423d0..e8799decc 100644
--- a/bin/ltldo.cc
+++ b/bin/ltldo.cc
@@ -125,7 +125,7 @@ parse_opt(int key, char* arg, struct argp_state*)
 
 namespace
 {
-  class xtranslator_runner: public translator_runner
+  class xtranslator_runner final: public translator_runner
   {
   public:
     xtranslator_runner(spot::bdd_dict_ptr dict)
@@ -209,7 +209,7 @@ namespace
   };
 
 
-  class processor: public job_processor
+  class processor final: public job_processor
   {
     spot::bdd_dict_ptr dict = spot::make_bdd_dict();
     xtranslator_runner runner;
diff --git a/bin/ltlfilt.cc b/bin/ltlfilt.cc
index caedbdfec..cd727abf5 100644
--- a/bin/ltlfilt.cc
+++ b/bin/ltlfilt.cc
@@ -465,7 +465,7 @@ std::unordered_set<spot::formula> fset_t;
 
 namespace
 {
-  class ltl_processor: public job_processor
+  class ltl_processor final: public job_processor
   {
   public:
     spot::tl_simplifier& simpl;
diff --git a/bin/ltlgrind.cc b/bin/ltlgrind.cc
index 0085804be..84bac6665 100644
--- a/bin/ltlgrind.cc
+++ b/bin/ltlgrind.cc
@@ -1,6 +1,6 @@
 // -*- coding: utf-8 -*-
-// Copyright (C) 2014, 2015 Laboratoire de Recherche et Développement de
-// l'Epita (LRDE).
+// Copyright (C) 2014, 2015, 2016 Laboratoire de Recherche et
+// Développement de l'Epita (LRDE).
 //
 // This file is part of Spot, a model checking library.
 //
@@ -108,7 +108,7 @@ static const argp_child children[] = {
 
 namespace
 {
-  class mutate_processor: public job_processor
+  class mutate_processor final: public job_processor
   {
   public:
     int
diff --git a/spot/misc/intvcmp2.cc b/spot/misc/intvcmp2.cc
index 204b74867..27e809c6d 100644
--- a/spot/misc/intvcmp2.cc
+++ b/spot/misc/intvcmp2.cc
@@ -1,6 +1,6 @@
 // -*- coding: utf-8 -*-
-// Copyright (C) 2011, 2013, 2014, 2015 Laboratoire de Recherche et
-// Développement de l'Epita (LRDE).
+// Copyright (C) 2011, 2013, 2014, 2015, 2016 Laboratoire de Recherche
+// et Développement de l'Epita (LRDE).
 //
 // This file is part of Spot, a model checking library.
 //
@@ -326,7 +326,7 @@ namespace spot
     };
 
 
-    class int_array_array_compression:
+    class int_array_array_compression final:
       public stream_compression_base<int_array_array_compression>
     {
     public:
@@ -497,7 +497,7 @@ namespace spot
     };
 
 
-    class int_array_array_decompression:
+    class int_array_array_decompression final:
       public stream_decompression_base<int_array_array_decompression>
     {
     public:
diff --git a/spot/misc/intvcomp.cc b/spot/misc/intvcomp.cc
index abac2a0f8..349e1185c 100644
--- a/spot/misc/intvcomp.cc
+++ b/spot/misc/intvcomp.cc
@@ -1,5 +1,5 @@
 // -*- coding: utf-8 -*-
-// Copyright (C) 2011, 2013, 2014 Laboratoire de Recherche et
+// Copyright (C) 2011, 2013, 2014, 2016 Laboratoire de Recherche et
 // Développement de l'Epita (LRDE).
 //
 // This file is part of Spot, a model checking library.
@@ -184,7 +184,7 @@ namespace spot
       unsigned int bits_left_;
     };
 
-    class int_array_vector_compression:
+    class int_array_vector_compression final:
       public stream_compression_base<int_array_vector_compression>
     {
     public:
@@ -233,7 +233,7 @@ namespace spot
       std::vector<unsigned int>* result_;
     };
 
-    class int_vector_vector_compression:
+    class int_vector_vector_compression final:
       public stream_compression_base<int_vector_vector_compression>
     {
     public:
@@ -277,7 +277,7 @@ namespace spot
       std::vector<unsigned int>& output_;
     };
 
-    class int_array_array_compression:
+    class int_array_array_compression final:
       public stream_compression_base<int_array_array_compression>
     {
     public:
@@ -521,7 +521,7 @@ namespace spot
       unsigned int buffer_bits_;
     };
 
-    class int_vector_vector_decompression:
+    class int_vector_vector_decompression final:
       public stream_decompression_base<int_vector_vector_decompression>
     {
     public:
@@ -572,7 +572,7 @@ namespace spot
       size_t size_;
     };
 
-    class int_vector_array_decompression:
+    class int_vector_array_decompression final:
       public stream_decompression_base<int_vector_array_decompression>
     {
     public:
@@ -622,7 +622,7 @@ namespace spot
       size_t size_;
     };
 
-    class int_array_array_decompression:
+    class int_array_array_decompression final:
       public stream_decompression_base<int_array_array_decompression>
     {
     public:
diff --git a/spot/taalgos/dot.cc b/spot/taalgos/dot.cc
index baf318a48..fe5c9ec83 100644
--- a/spot/taalgos/dot.cc
+++ b/spot/taalgos/dot.cc
@@ -30,7 +30,7 @@ namespace spot
 {
   namespace
   {
-    class dotty_bfs : public ta_reachable_iterator_breadth_first
+    class dotty_bfs final: public ta_reachable_iterator_breadth_first
     {
       void
       parse_opts(const char* options)
diff --git a/spot/taalgos/statessetbuilder.cc b/spot/taalgos/statessetbuilder.cc
index cd94aa33d..061376996 100644
--- a/spot/taalgos/statessetbuilder.cc
+++ b/spot/taalgos/statessetbuilder.cc
@@ -1,5 +1,5 @@
 // -*- coding: utf-8 -*-
-// Copyright (C) 2010, 2014 Laboratoire de Recherche et Développement
+// Copyright (C) 2010, 2014, 2016 Laboratoire de Recherche et Développement
 // de l'Epita (LRDE).
 //
 // This file is part of Spot, a model checking library.
@@ -26,7 +26,8 @@ namespace spot
 {
   namespace
   {
-    class states_set_builder_bfs : public ta_reachable_iterator_breadth_first
+    class states_set_builder_bfs final:
+      public ta_reachable_iterator_breadth_first
     {
     public:
       states_set_builder_bfs(const const_ta_ptr& a) :
diff --git a/spot/taalgos/stats.cc b/spot/taalgos/stats.cc
index b63fd0109..c2a7087e9 100644
--- a/spot/taalgos/stats.cc
+++ b/spot/taalgos/stats.cc
@@ -1,5 +1,5 @@
 // -*- coding: utf-8 -*-
-// Copyright (C) 2008, 2014, 2015 Laboratoire de Recherche et
+// Copyright (C) 2008, 2014, 2015, 2016 Laboratoire de Recherche et
 // Développement de l'Epita (LRDE).
 // Copyright (C) 2004 Laboratoire d'Informatique de Paris 6 (LIP6),
 // département Systèmes Répartis Coopératifs (SRC), Université Pierre
@@ -29,7 +29,7 @@ namespace spot
 {
   namespace
   {
-    class stats_bfs : public ta_reachable_iterator_breadth_first
+    class stats_bfs final: public ta_reachable_iterator_breadth_first
     {
     public:
       stats_bfs(const const_ta_ptr a, ta_statistics& s) :
diff --git a/spot/tl/relabel.cc b/spot/tl/relabel.cc
index 1eec38a19..05270453e 100644
--- a/spot/tl/relabel.cc
+++ b/spot/tl/relabel.cc
@@ -229,7 +229,7 @@ namespace spot
 
     // Convert the formula's syntax tree into an undirected graph
     // labeled by subformulas.
-    class formula_to_fgraph final
+    class formula_to_fgraph
     {
     public:
       fgraph& g;
diff --git a/spot/tl/simplify.cc b/spot/tl/simplify.cc
index db7615028..af3528772 100644
--- a/spot/tl/simplify.cc
+++ b/spot/tl/simplify.cc
@@ -39,7 +39,7 @@ namespace spot
   typedef std::vector<formula> vec;
 
   // The name of this class is public, but not its contents.
-  class tl_simplifier_cache
+  class tl_simplifier_cache final
   {
     typedef std::unordered_map<formula, formula> f2f_map;
     typedef std::unordered_map<formula, bdd> f2b_map;
diff --git a/spot/tl/snf.cc b/spot/tl/snf.cc
index 1ed89accf..0fe79ff41 100644
--- a/spot/tl/snf.cc
+++ b/spot/tl/snf.cc
@@ -1,5 +1,5 @@
 // -*- coding: utf-8 -*-
-// Copyright (C) 2012, 2014, 2015 Laboratoire de Recherche et
+// Copyright (C) 2012, 2014, 2015, 2016 Laboratoire de Recherche et
 // Developpement de l'Epita (LRDE).
 //
 // This file is part of Spot, a model checking library.
@@ -26,7 +26,7 @@ namespace spot
     // E°  if bounded=false
     // E^□ if nounded=true
     template<bool bounded>
-    class snf_visitor
+    class snf_visitor final
     {
     protected:
       formula result_;
diff --git a/spot/twa/bdddict.cc b/spot/twa/bdddict.cc
index cb972055e..e92c62cc8 100644
--- a/spot/twa/bdddict.cc
+++ b/spot/twa/bdddict.cc
@@ -1,6 +1,6 @@
 // -*- coding: utf-8 -*-
-// Copyright (C) 2009, 2012, 2013, 2014, 2015 Laboratoire de Recherche
-// et Développement de l'Epita (LRDE).
+// Copyright (C) 2009, 2012, 2013, 2014, 2015, 2016 Laboratoire de
+// Recherche et Développement de l'Epita (LRDE).
 // Copyright (C) 2003, 2004, 2005, 2006 Laboratoire d'Informatique de
 // Paris 6 (LIP6), département Systèmes Répartis Coopératifs (SRC),
 // Université Pierre et Marie Curie.
@@ -39,7 +39,7 @@ namespace spot
   {
   }
 
-  class bdd_dict_priv: public bdd_allocator
+  class bdd_dict_priv final: public bdd_allocator
   {
   public:
 
diff --git a/spot/twa/twaproduct.cc b/spot/twa/twaproduct.cc
index a7ee9153c..03957aed1 100644
--- a/spot/twa/twaproduct.cc
+++ b/spot/twa/twaproduct.cc
@@ -147,7 +147,8 @@ namespace spot
 
 
     /// \brief Iterate over the successors of a product computed on the fly.
-    class twa_succ_iterator_product: public twa_succ_iterator_product_common
+    class twa_succ_iterator_product final:
+      public twa_succ_iterator_product_common
     {
     public:
       twa_succ_iterator_product(twa_succ_iterator* left,
@@ -212,7 +213,7 @@ namespace spot
 
     /// Iterate over the successors of a product computed on the fly.
     /// This one assumes that LEFT is an iterator over a Kripke structure
-    class twa_succ_iterator_product_kripke:
+    class twa_succ_iterator_product_kripke final:
       public twa_succ_iterator_product_common
     {
     public:
diff --git a/spot/twaalgos/degen.cc b/spot/twaalgos/degen.cc
index 346768104..b73f2afc1 100644
--- a/spot/twaalgos/degen.cc
+++ b/spot/twaalgos/degen.cc
@@ -57,7 +57,7 @@ namespace spot
 
     // Acceptance set common to all outgoing edges (of the same
     // SCC -- we do not care about the other) of some state.
-    class outgoing_acc
+    class outgoing_acc final
     {
       const_twa_graph_ptr a_;
       typedef std::tuple<acc_cond::mark_t,
@@ -125,7 +125,7 @@ namespace spot
     };
 
     // Order of accepting sets (for one SCC)
-    class acc_order
+    class acc_order final
     {
       std::vector<unsigned> order_;
       acc_cond::mark_t found_;
@@ -162,7 +162,7 @@ namespace spot
     };
 
     // Accepting order for each SCC
-    class scc_orders
+    class scc_orders final
     {
       std::map<int, acc_order> orders_;
       bool skip_levels_;
diff --git a/spot/twaalgos/determinize.cc b/spot/twaalgos/determinize.cc
index d1460d382..f88266ce6 100644
--- a/spot/twaalgos/determinize.cc
+++ b/spot/twaalgos/determinize.cc
@@ -46,7 +46,7 @@ namespace spot
                          std::vector<size_t>& nb_braces);
   };
 
-  class safra_state
+  class safra_state final
   {
   public:
     using state_t = unsigned;
diff --git a/spot/twaalgos/dot.cc b/spot/twaalgos/dot.cc
index 16d7294dc..01c51b075 100644
--- a/spot/twaalgos/dot.cc
+++ b/spot/twaalgos/dot.cc
@@ -44,7 +44,7 @@ namespace spot
   {
     constexpr int MAX_BULLET = 20;
 
-    class dotty_output
+    class dotty_output final
     {
       std::ostream& os_;
       bool opt_force_acc_trans_ = false;
diff --git a/spot/twaalgos/emptiness.cc b/spot/twaalgos/emptiness.cc
index 967167d9b..daf604b67 100644
--- a/spot/twaalgos/emptiness.cc
+++ b/spot/twaalgos/emptiness.cc
@@ -280,7 +280,7 @@ namespace spot
 
   namespace
   {
-    class shortest_path: public bfs_steps
+    class shortest_path final: public bfs_steps
     {
     public:
       shortest_path(const const_twa_ptr& a)
diff --git a/spot/twaalgos/gtec/ce.cc b/spot/twaalgos/gtec/ce.cc
index 2ba782f51..443c11227 100644
--- a/spot/twaalgos/gtec/ce.cc
+++ b/spot/twaalgos/gtec/ce.cc
@@ -28,7 +28,7 @@ namespace spot
 {
   namespace
   {
-    class shortest_path: public bfs_steps
+    class shortest_path final: public bfs_steps
     {
     public:
       shortest_path(const state_set* t,
diff --git a/spot/twaalgos/ltl2tgba_fm.cc b/spot/twaalgos/ltl2tgba_fm.cc
index 184efde6a..05bb7a53b 100644
--- a/spot/twaalgos/ltl2tgba_fm.cc
+++ b/spot/twaalgos/ltl2tgba_fm.cc
@@ -102,7 +102,7 @@ namespace spot
 
     class translate_dict;
 
-    class ratexp_to_dfa
+    class ratexp_to_dfa final
     {
       typedef twa_graph::namer<formula> namer;
     public:
@@ -129,7 +129,7 @@ namespace spot
     //   "a" variables are promises (written "a" in the paper)
     //   "next" variables are X's operands (the "r_X" variables from the paper)
     //   "var" variables are atomic propositions.
-    class translate_dict
+    class translate_dict final
     {
     public:
 
@@ -1063,7 +1063,7 @@ namespace spot
     // Duret-Lutz's paper "LTL Translation Improvements in Spot 1.0"
     // (IJCCBS 2014), for the optimization.  The PSL stuff is
     // unpublished yet.
-    class ltl_trad_visitor
+    class ltl_trad_visitor final
     {
     public:
       ltl_trad_visitor(translate_dict& dict, bool mark_all = false,
@@ -1663,7 +1663,7 @@ namespace spot
 
     // Check whether a formula can be part of a fair loop.
     // Cache the result for efficiency.
-    class possible_fair_loop_checker
+    class possible_fair_loop_checker final
     {
     public:
       bool
@@ -1680,7 +1680,7 @@ namespace spot
       pfl_map pfl_;
     };
 
-    class formula_canonizer
+    class formula_canonizer final
     {
     public:
       formula_canonizer(translate_dict& d,
diff --git a/spot/twaalgos/magic.cc b/spot/twaalgos/magic.cc
index 108b12457..f92b88a88 100644
--- a/spot/twaalgos/magic.cc
+++ b/spot/twaalgos/magic.cc
@@ -47,7 +47,7 @@ namespace spot
     /// \brief Emptiness checker on spot::tgba automata having at most one
     /// acceptance condition (i.e. a TBA).
     template <typename heap>
-    class magic_search_ : public emptiness_check, public ec_statistics
+    class magic_search_ final : public emptiness_check, public ec_statistics
     {
     public:
       /// \brief Initialize the Magic Search algorithm on the automaton \a a
@@ -424,12 +424,12 @@ namespace spot
       };
     };
 
-    class explicit_magic_search_heap
+    class explicit_magic_search_heap final
     {
     public:
       enum { Safe = 1 };
 
-      class color_ref
+      class color_ref final
       {
       public:
         color_ref(color* c) :p(c)
@@ -507,12 +507,12 @@ namespace spot
       state_map<color> h;
     };
 
-    class bsh_magic_search_heap
+    class bsh_magic_search_heap final
     {
     public:
       enum { Safe = 0 };
 
-      class color_ref
+      class color_ref final
       {
       public:
         color_ref(unsigned char *b, unsigned char o): base(b), offset(o*2)
diff --git a/spot/twaalgos/neverclaim.cc b/spot/twaalgos/neverclaim.cc
index 4f5a59e31..296f02344 100644
--- a/spot/twaalgos/neverclaim.cc
+++ b/spot/twaalgos/neverclaim.cc
@@ -1,6 +1,6 @@
 // -*- coding: utf-8 -*-
-// Copyright (C) 2009, 2011, 2012, 2014, 2015 Laboratoire de Recherche et
-// Développement de l'Epita (LRDE).
+// Copyright (C) 2009, 2011, 2012, 2014, 2015, 2016 Laboratoire de
+// Recherche et Développement de l'Epita (LRDE).
 // Copyright (C) 2004 Laboratoire d'Informatique de Paris 6 (LIP6),
 // département Systèmes Répartis Coopératifs (SRC), Université Pierre
 // et Marie Curie.
@@ -33,7 +33,7 @@ namespace spot
 {
   namespace
   {
-    class never_claim_output
+    class never_claim_output final
     {
     public:
       std::ostream& os_;
diff --git a/spot/twaalgos/se05.cc b/spot/twaalgos/se05.cc
index 49127bc0b..8ed040ddd 100644
--- a/spot/twaalgos/se05.cc
+++ b/spot/twaalgos/se05.cc
@@ -325,7 +325,7 @@ namespace spot
         return false;
       }
 
-      class result_from_stack: public emptiness_check_result,
+      class result_from_stack final: public emptiness_check_result,
         public acss_statistics
       {
       public:
@@ -436,14 +436,14 @@ namespace spot
       };
     };
 
-    class explicit_se05_search_heap
+    class explicit_se05_search_heap final
     {
       typedef state_set hcyan_type;
       typedef state_map<color> hash_type;
     public:
       enum { Safe = 1 };
 
-      class color_ref
+      class color_ref final
       {
       public:
         color_ref(hash_type* h, hcyan_type* hc, const state* s)
@@ -569,7 +569,7 @@ namespace spot
       hcyan_type hc; // associate to each cyan state its weight
     };
 
-    class bsh_se05_search_heap
+    class bsh_se05_search_heap final
     {
     private:
       typedef std::unordered_set<const state*,
@@ -577,7 +577,7 @@ namespace spot
     public:
       enum { Safe = 0 };
 
-      class color_ref
+      class color_ref final
       {
       public:
         color_ref(hcyan_type* h, const state* st,
diff --git a/spot/twaalgos/simulation.cc b/spot/twaalgos/simulation.cc
index 4c6dd6c71..3c238edf8 100644
--- a/spot/twaalgos/simulation.cc
+++ b/spot/twaalgos/simulation.cc
@@ -1,6 +1,6 @@
 // -*- coding: utf-8 -*-
-// Copyright (C) 2012, 2013, 2014, 2015 Laboratoire de Recherche et
-// Développement de l'Epita (LRDE).
+// Copyright (C) 2012, 2013, 2014, 2015, 2016 Laboratoire de Recherche
+// et Développement de l'Epita (LRDE).
 //
 // This file is part of Spot, a model checking library.
 //
@@ -155,7 +155,7 @@ namespace spot
     // The direct_simulation. If Cosimulation is true, we are doing a
     // cosimulation.
     template <bool Cosimulation, bool Sba>
-    class direct_simulation
+    class direct_simulation final
     {
     protected:
       // Shortcut used in update_po and go_to_next_it.
diff --git a/spot/twaalgos/tau03.cc b/spot/twaalgos/tau03.cc
index 4de71a708..d69a66b3b 100644
--- a/spot/twaalgos/tau03.cc
+++ b/spot/twaalgos/tau03.cc
@@ -276,10 +276,10 @@ namespace spot
 
     };
 
-    class explicit_tau03_search_heap
+    class explicit_tau03_search_heap final
     {
     public:
-      class color_ref
+      class color_ref final
       {
       public:
         color_ref(color* c, acc_cond::mark_t* a) :p(c), acc(a)
diff --git a/spot/twaalgos/tau03opt.cc b/spot/twaalgos/tau03opt.cc
index a597a5355..15a6659cc 100644
--- a/spot/twaalgos/tau03opt.cc
+++ b/spot/twaalgos/tau03opt.cc
@@ -395,12 +395,12 @@ namespace spot
 
     };
 
-    class explicit_tau03_opt_search_heap
+    class explicit_tau03_opt_search_heap final
     {
       typedef state_map<std::pair<weight, acc_cond::mark_t>> hcyan_type;
       typedef state_map<std::pair<color, acc_cond::mark_t>> hash_type;
     public:
-      class color_ref
+      class color_ref final
       {
       public:
         color_ref(hash_type* h, hcyan_type* hc, const state* s,