Introduce tgba::release_iter().

Instead of "delete iter;" we now do "aut->release_iter(iter);" to
give the iterator back to the automaton.  The TGBA classes now
reuse a previously returned tgba_succ_iterator to answer a succ_iter()
call, therefore avoiding (1) memory allocation, as well as (2) vtable
and other constant member initialization.

* src/tgba/tgba.hh, src/tgba/tgba.cc (release_iter, iter_cache_):
Implement a release_iter() that stores the released iterator
in iter_cache_.
* src/tgba/succiter.hh (internal::succ_iterable): Move...
* src/tgba/tgba.hh (tgba::succ_iterable): ... here. And use
release_iter().

* iface/dve2/dve2.cc, src/kripke/kripke.cc, src/kripke/kripke.hh,
src/tgba/succiterconcrete.cc, src/tgba/succiterconcrete.hh,
src/tgba/taatgba.hh, src/tgba/tgbabddconcrete.cc,
src/tgba/tgbaexplicit.hh, src/tgba/tgbamask.cc, src/tgba/tgbaproduct.cc,
src/tgba/tgbaproxy.cc, src/tgba/tgbascc.cc, src/tgba/tgbatba.cc,
src/tgba/tgbaunion.cc, src/tgba/tgbaunion.hh, src/tgba/wdbacomp.cc,
src/tgbaalgos/bfssteps.cc, src/tgbaalgos/compsusp.cc,
src/tgbaalgos/cycles.cc, src/tgbaalgos/dtbasat.cc,
src/tgbaalgos/dtgbasat.cc, src/tgbaalgos/gtec/gtec.cc,
src/tgbaalgos/gv04.cc, src/tgbaalgos/isweakscc.cc,
src/tgbaalgos/lbtt.cc, src/tgbaalgos/ltl2tgba_fm.cc,
src/tgbaalgos/magic.cc, src/tgbaalgos/ndfs_result.hxx,
src/tgbaalgos/neverclaim.cc, src/tgbaalgos/reachiter.cc,
src/tgbaalgos/replayrun.cc, src/tgbaalgos/safety.cc,
src/tgbaalgos/scc.cc, src/tgbaalgos/se05.cc,
src/tgbaalgos/simulation.cc, src/tgbaalgos/tau03.cc,
src/tgbaalgos/tau03opt.cc: Use release_iter() instead of deleting
iterators, and used recycle iter_cache_ in implementations of
tgba::succ_iter().

iface/dve2/dve2.cc

@@ -1,5 +1,5 @@
 // -*- coding: utf-8 -*-
-// Copyright (C) 2011, 2012 Laboratoire de Recherche et Développement
+// Copyright (C) 2011, 2012, 2014 Laboratoire de Recherche et Développement
 // de l'Epita (LRDE)
 //
 // This file is part of Spot, a model checking library.
@@ -214,9 +214,8 @@ namespace spot
 
       ~callback_context()
       {
-	callback_context::transitions_t::const_iterator it;
+	for (auto t: transitions)
-	for (it = transitions.begin(); it != transitions.end(); ++it)
+	  t->destroy();
-	  (*it)->destroy();
       }
     };
 
@@ -260,6 +259,13 @@ namespace spot
       {
       }
 
+      void recycle(const callback_context* cc, bdd cond)
+      {
+	delete cc_;
+	cc_ = cc;
+	kripke_succ_iterator::recycle(cond);
+      }
+
       ~dve2_succ_iterator()
       {
 	delete cc_;
@@ -661,6 +667,11 @@ namespace spot
 
       ~dve2_kripke()
       {
+	if (iter_cache_)
+	  {
+	    delete iter_cache_;
+	    iter_cache_ = nullptr;
+	  }
 	delete[] format_filter_;
 	delete[] vname_;
 	if (compress_)
@@ -857,6 +868,14 @@ namespace spot
 	      cc->transitions.push_back(local_state->clone());
 	  }
 
+	if (iter_cache_)
+	  {
+	    dve2_succ_iterator* it =
+	      down_cast<dve2_succ_iterator*>(iter_cache_);
+	    it->recycle(cc, scond);
+	    iter_cache_ = nullptr;
+	    return it;
+	  }
 	return new dve2_succ_iterator(cc, scond);
       }
 

src/kripke/kripke.cc

@@ -1,4 +1,6 @@
-// Copyright (C) 2009, 2010 Laboratoire de Recherche et Developpement de l'Epita
+// -*- coding: utf-8 -*-
+// Copyright (C) 2009, 2010, 2014 Laboratoire de Recherche et
+// Developpement de l'Epita
 //
 // This file is part of Spot, a model checking library.
 //
@@ -20,11 +22,6 @@
 namespace spot
 {
 
-  kripke_succ_iterator::kripke_succ_iterator(const bdd& cond)
-    : cond_(cond)
-  {
-  }
-
   kripke_succ_iterator::~kripke_succ_iterator()
   {
   }

src/kripke/kripke.hh

@@ -1,5 +1,5 @@
 // -*- coding: utf-8 -*-
-// Copyright (C) 2009, 2010, 2013 Laboratoire de Recherche et
+// Copyright (C) 2009, 2010, 2013, 2014 Laboratoire de Recherche et
 // Developpement de l'Epita
 //
 // This file is part of Spot, a model checking library.
@@ -48,7 +48,16 @@ namespace spot
     ///
     /// The \a cond argument will be the one returned
     /// by kripke_succ_iterator::current_condition().
-    kripke_succ_iterator(const bdd& cond);
+    kripke_succ_iterator(const bdd& cond)
+      : cond_(cond)
+    {
+    }
+
+    void recycle(const bdd& cond)
+    {
+      cond_ = cond;
+    }
+
     virtual ~kripke_succ_iterator();
 
     virtual bdd current_condition() const;

src/tgba/succiter.hh

@@ -27,6 +27,8 @@
 
 namespace spot
 {
+  class tgba;
+
   /// \ingroup tgba_essentials
   /// \brief Iterate over the successors of a state.
   ///
@@ -100,8 +102,6 @@ namespace spot
     //@}
   };
 
-  class tgba;
-
   namespace internal
   {
     struct SPOT_API succ_iterator
@@ -137,34 +137,6 @@ namespace spot
 	  it_ = nullptr;
       }
     };
-
-    class SPOT_API succ_iterable
-    {
-    protected:
-      const tgba* aut_;
-      tgba_succ_iterator* it_;
-    public:
-      succ_iterable(const tgba* aut, tgba_succ_iterator* it)
-	: aut_(aut), it_(it)
-      {
-      }
-
-      ~succ_iterable()
-      {
-	delete it_;
-      }
-
-      succ_iterator begin()
-      {
-	it_->first();
-	return it_->done() ? nullptr : it_;
-      }
-
-      succ_iterator end()
-      {
-	return nullptr;
-      }
-    };
   }
 }
 

src/tgba/succiterconcrete.cc

@@ -1,7 +1,8 @@
-// Copyright (C) 2009 Laboratoire de Recherche et Développement
+// -*- coding: utf-8 -*-
+// Copyright (C) 2009, 2014 Laboratoire de Recherche et Développement
 // de l'Epita (LRDE).
 // Copyright (C) 2003 Laboratoire d'Informatique de Paris 6 (LIP6),
-// département Systèmes Répartis Coopératifs (SRC), Université Pierre
+// département Systèmes Répartis Coopératifs (SRC), Université Pierre
 // et Marie Curie.
 //
 // This file is part of Spot, a model checking library.
@@ -24,15 +25,6 @@
 
 namespace spot
 {
-  tgba_succ_iterator_concrete::tgba_succ_iterator_concrete
-  (const tgba_bdd_core_data& d, bdd successors)
-    : data_(d),
-      succ_set_(successors),
-      succ_set_left_(successors),
-      current_(bddfalse)
-  {
-  }
-
   tgba_succ_iterator_concrete::~tgba_succ_iterator_concrete()
   {
   }

src/tgba/succiterconcrete.hh

@@ -1,5 +1,5 @@
 // -*- coding: utf-8 -*-
-// Copyright (C) 2013 Laboratoire de Recherche et Developpement de
+// Copyright (C) 2013, 2014 Laboratoire de Recherche et Developpement de
 // l'Epita (LRDE).
 // Copyright (C) 2003, 2004, 2005  Laboratoire d'Informatique de Paris 6 (LIP6),
 // département Systèmes Répartis Coopératifs (SRC), Université Pierre
@@ -45,7 +45,19 @@ namespace spot
     /// \param d The core data of the automata.
     ///   These contains sets of variables useful to split a BDD, and
     ///   compute acceptance conditions.
-    tgba_succ_iterator_concrete(const tgba_bdd_core_data& d, bdd successors);
+    tgba_succ_iterator_concrete(const tgba_bdd_core_data& d, bdd successors)
+      : data_(d)
+    {
+      recycle(successors);
+    }
+
+    void recycle(bdd successors)
+    {
+      succ_set_ = successors;
+      succ_set_left_ = successors;
+      current_ = bddfalse;
+    }
+
     virtual ~tgba_succ_iterator_concrete();
 
     // iteration

src/tgba/taatgba.hh

@@ -1,5 +1,5 @@
 // -*- coding: utf-8 -*-
-// Copyright (C) 2009, 2011, 2012, 2013 Laboratoire de Recherche et
+// Copyright (C) 2009, 2011, 2012, 2013, 2014 Laboratoire de Recherche et
 // Développement de l'Epita (LRDE).
 //
 // This file is part of Spot, a model checking library.

src/tgba/tgba.cc

@@ -1,7 +1,8 @@
-// Copyright (C) 2011 Laboratoire de Recherche et Developpement de
+// -*- coding: utf-8 -*-
+// Copyright (C) 2011, 2014 Laboratoire de Recherche et Developpement de
 // l'EPITA (LRDE).
 // Copyright (C) 2003, 2004, 2005  Laboratoire d'Informatique de Paris 6 (LIP6),
-// département Systèmes Répartis Coopératifs (SRC), Université Pierre
+// département Systèmes Répartis Coopératifs (SRC), Université Pierre
 // et Marie Curie.
 //
 // This file is part of Spot, a model checking library.
@@ -24,7 +25,8 @@
 namespace spot
 {
   tgba::tgba()
-    : last_support_conditions_input_(0),
+    : iter_cache_(nullptr),
+      last_support_conditions_input_(0),
       last_support_variables_input_(0),
       num_acc_(-1)
   {
@@ -36,6 +38,7 @@ namespace spot
       last_support_conditions_input_->destroy();
     if (last_support_variables_input_)
       last_support_variables_input_->destroy();
+    delete iter_cache_;
   }
 
   bdd

src/tgba/tgba.hh

@@ -71,8 +71,48 @@ namespace spot
   {
   protected:
     tgba();
+    // Any iterator returned via release_iter.
+    mutable tgba_succ_iterator* iter_cache_;
 
   public:
+
+#ifndef SWIG
+    class succ_iterable
+    {
+    protected:
+      const tgba* aut_;
+      tgba_succ_iterator* it_;
+    public:
+      succ_iterable(const tgba* aut, tgba_succ_iterator* it)
+	: aut_(aut), it_(it)
+      {
+      }
+
+      succ_iterable(succ_iterable&& other)
+	: aut_(other.aut_), it_(other.it_)
+      {
+	other.it_ = nullptr;
+      }
+
+      ~succ_iterable()
+      {
+	if (it_)
+	  aut_->release_iter(it_);
+      }
+
+      internal::succ_iterator begin()
+      {
+	it_->first();
+	return it_->done() ? nullptr : it_;
+      }
+
+      internal::succ_iterator end()
+      {
+	return nullptr;
+      }
+    };
+#endif
+
     virtual ~tgba();
 
     /// \brief Get the initial state of the automaton.
@@ -111,15 +151,29 @@ namespace spot
 	      const state* global_state = nullptr,
 	      const tgba* global_automaton = nullptr) const = 0;
 
+#ifndef SWIG
     /// \brief Build an iterable over the successors of \a s.
     ///
     /// This is meant to be used as
     /// <code>for (auto i: aut->out(s)) { /* i->current_state() */ }</code>.
-    internal::succ_iterable
+    succ_iterable
     succ(const state* s) const
     {
       return {this, succ_iter(s)};
     }
+#endif
+
+    /// \brief Release an iterator after usage.
+    ///
+    /// This iterator can then be reused by succ_iter() to avoid
+    /// memory allocation.
+    void release_iter(tgba_succ_iterator* i) const
+    {
+      if (iter_cache_)
+	delete i;
+      else
+	iter_cache_ = i;
+    }
 
     /// \brief Get a formula that must hold whatever successor is taken.
     ///

src/tgba/tgbabddconcrete.cc

@@ -1,7 +1,8 @@
-// Copyright (C) 2011 Laboratoire de Recherche et Développement de
+// -*- coding: utf-8 -*-
-// l'Epita (LRDE).
+// Copyright (C) 2011, 2014 Laboratoire de Recherche et Développement
+// de l'Epita (LRDE).
 // Copyright (C) 2003 Laboratoire d'Informatique de Paris 6 (LIP6),
-// département Systèmes Répartis Coopératifs (SRC), Université Pierre
+// département Systèmes Répartis Coopératifs (SRC), Université Pierre
 // et Marie Curie.
 //
 // This file is part of Spot, a model checking library.
@@ -107,6 +108,15 @@ namespace spot
 	bdd global_conds = global_automaton->support_conditions(global_state);
 	succ_set = bdd_appexcomp(succ_set, global_conds, bddop_and, varused);
       }
+    // Do not allocate an iterator if we can reuse one.
+    if (iter_cache_)
+      {
+	tgba_succ_iterator_concrete* res =
+	  down_cast<tgba_succ_iterator_concrete*>(iter_cache_);
+	iter_cache_ = nullptr;
+	res->recycle(succ_set);
+	return res;
+      }
     return new tgba_succ_iterator_concrete(data_, succ_set);
   }
 

src/tgba/tgbaexplicit.hh

@@ -1,6 +1,6 @@
 // -*- coding: utf-8 -*-
-// Copyright (C) 2009, 2010, 2011, 2012, 2013 Laboratoire de Recherche
+// Copyright (C) 2009, 2010, 2011, 2012, 2013, 2014 Laboratoire de
-// et Développement de l'Epita.
+// Recherche et Développement de l'Epita.
 // Copyright (C) 2003, 2004, 2006 Laboratoire d'Informatique de Paris
 // 6 (LIP6), département Systèmes Répartis Coopératifs (SRC),
 // Université Pierre et Marie Curie.
@@ -202,6 +202,12 @@ namespace spot
     {
     }
 
+    void recycle(const State* start, bdd all_acc)
+    {
+      start_ = start;
+      all_acceptance_conditions_ = all_acc;
+    }
+
     virtual void first()
     {
       it_ = start_->successors.begin();
@@ -508,6 +514,14 @@ namespace spot
       (void) global_state;
       (void) global_automaton;
 
+      if (this->iter_cache_)
+	{
+	  tgba_explicit_succ_iterator<State>* it =
+	    down_cast<tgba_explicit_succ_iterator<State>*>(this->iter_cache_);
+	  it->recycle(s, this->all_acceptance_conditions());
+	  this->iter_cache_ = nullptr;
+	  return it;
+	}
       return
 	new tgba_explicit_succ_iterator<State>(s,
 					       this

src/tgba/tgbamask.cc

@@ -141,7 +141,16 @@ namespace spot
 		       const state*,
 		       const tgba*) const
   {
-    succ_iter_filtered* res = new succ_iter_filtered;
+    succ_iter_filtered* res;
+    if (iter_cache_)
+      {
+	res = down_cast<succ_iter_filtered*>(iter_cache_);
+	iter_cache_ = nullptr;
+      }
+    else
+      {
+	res = new succ_iter_filtered;
+      }
     for (auto it: original_->succ(local_state))
       {
 	const state* s = it->current_state();

src/tgba/tgbaproduct.cc

@@ -1,8 +1,9 @@
-// Copyright (C) 2009, 2011, 2012 Laboratoire de Recherche et
+// -*- coding: utf-8 -*-
-// Développement de l'Epita (LRDE).
+// Copyright (C) 2009, 2011, 2012, 2014 Laboratoire de Recherche et
+// Développement de l'Epita (LRDE).
 // Copyright (C) 2003, 2004, 2006 Laboratoire d'Informatique de
-// Paris 6 (LIP6), département Systèmes Répartis Coopératifs (SRC),
+// Paris 6 (LIP6), département Systèmes Répartis Coopératifs (SRC),
-// Université Pierre et Marie Curie.
+// Université Pierre et Marie Curie.
 //
 // This file is part of Spot, a model checking library.
 //
@@ -88,6 +89,15 @@ namespace spot
       {
       }
 
+      void recycle(const tgba* l, tgba_succ_iterator* left,
+		   const tgba* r, tgba_succ_iterator* right)
+      {
+	l->release_iter(left_);
+	left_ = left;
+	r->release_iter(right_);
+	right_ = right;
+      }
+
       virtual ~tgba_succ_iterator_product_common()
       {
 	delete left_;
@@ -390,6 +400,15 @@ namespace spot
     tgba_succ_iterator* ri = right_->succ_iter(s->right(),
 					       global_state, global_automaton);
 
+    if (iter_cache_)
+      {
+	tgba_succ_iterator_product_common* it =
+	  down_cast<tgba_succ_iterator_product_common*>(iter_cache_);
+	it->recycle(left_, li, right_, ri);
+	iter_cache_ = nullptr;
+	return it;
+      }
+
     fixed_size_pool* p = const_cast<fixed_size_pool*>(&pool_);
     if (left_kripke_)
       return new tgba_succ_iterator_product_kripke(li, ri, p);

src/tgba/tgbaproxy.cc

@@ -1,4 +1,5 @@
-// Copyright (C) 2013 Laboratoire de Recherche et
+// -*- coding: utf-8 -*-
+// Copyright (C) 2013, 2014 Laboratoire de Recherche et
 // Développement de l'Epita (LRDE).
 //
 // This file is part of Spot, a model checking library.
@@ -41,6 +42,11 @@ namespace spot
 			const state* global_state,
 			const tgba* global_automaton) const
   {
+    if (iter_cache_)
+      {
+	original_->release_iter(iter_cache_);
+	iter_cache_ = nullptr;
+      }
     return original_->succ_iter(local_state, global_state, global_automaton);
   }
 

src/tgba/tgbascc.cc

@@ -1,5 +1,5 @@
 // -*- coding: utf-8 -*-
-// Copyright (C) 2009, 2012, 2013 Laboratoire de recherche et
+// Copyright (C) 2009, 2012, 2013, 2014 Laboratoire de recherche et
 // développement de l'Epita.
 //
 // This file is part of Spot, a model checking library.
@@ -50,6 +50,11 @@ namespace spot
 		      const state* global_state,
 		      const tgba* global_automaton) const
   {
+    if (iter_cache_)
+      {
+	aut_->release_iter(iter_cache_);
+	iter_cache_ = nullptr;
+      }
     return aut_->succ_iter(local_state, global_state, global_automaton);
   }
 

src/tgba/tgbatba.cc

@@ -170,14 +170,29 @@ namespace spot
       typedef tgba_tba_proxy::cycle_list::const_iterator iterator;
     public:
       tgba_tba_proxy_succ_iterator(const state* rs,
-				   tgba_succ_iterator* it,
+				   tgba::succ_iterable&& iterable,
 				   iterator expected,
 				   const list& cycle,
 				   bdd the_acceptance_cond,
 				   const tgba_tba_proxy* aut)
 	: the_acceptance_cond_(the_acceptance_cond)
       {
-	for (it->first(); !it->done(); it->next())
+	recycle(rs, std::move(iterable), expected, cycle, aut);
+      }
+
+      void recycle(const state* rs,
+		   tgba::succ_iterable&& iterable,
+		   iterator expected,
+		   const list& cycle,
+		   const tgba_tba_proxy* aut)
+      {
+	if (!transmap_.empty())
+	  {
+	    translist_.clear();
+	    transmap_.clear();
+	  }
+
+	for (auto it: iterable)
 	  {
 	    bool accepting;
 	    bdd acc = it->current_acceptance_conditions();
@@ -324,20 +339,11 @@ namespace spot
 		dest->destroy();
 	      }
 	  }
-	delete it;
       }
 
       virtual
       ~tgba_tba_proxy_succ_iterator()
       {
-	for (transmap_t::const_iterator i = transmap_.begin();
-	     i != transmap_.end();)
-	  {
-	    const state* d = i->first.first;
-	    // Advance i before deleting d.
-	    ++i;
-	    d->destroy();
-	  }
       }
 
       // iteration
@@ -492,17 +498,23 @@ namespace spot
 
   tgba_succ_iterator*
   tgba_tba_proxy::succ_iter(const state* local_state,
-			    const state* global_state,
+			    const state*, const tgba*) const
-			    const tgba* global_automaton) const
   {
     const state_tba_proxy* s =
       down_cast<const state_tba_proxy*>(local_state);
     assert(s);
-
     const state* rs = s->real_state();
-    tgba_succ_iterator* it = a_->succ_iter(rs, global_state, global_automaton);
 
-    return new tgba_tba_proxy_succ_iterator(rs, it,
+    if (iter_cache_)
+      {
+	tgba_tba_proxy_succ_iterator* res =
+	  down_cast<tgba_tba_proxy_succ_iterator*>(iter_cache_);
+	res->recycle(rs, a_->succ(rs),
+		     s->acceptance_iterator(), acc_cycle_, this);
+	iter_cache_ = nullptr;
+	return res;
+      }
+    return new tgba_tba_proxy_succ_iterator(rs, a_->succ(rs),
 					    s->acceptance_iterator(),
 					    acc_cycle_, the_acceptance_cond_,
 					    this);

src/tgba/tgbaunion.cc

@@ -1,5 +1,6 @@
-// Copyright (C) 2009, 2011 Laboratoire de Recherche et Développement
+// -*- coding: utf-8 -*-
-// de l'Epita (LRDE).
+// Copyright (C) 2009, 2011, 2014 Laboratoire de Recherche et
+// Développement de l'Epita (LRDE).
 //
 // This file is part of Spot, a model checking library.
 //
@@ -94,6 +95,16 @@ namespace spot
   {
   }
 
+  void
+  tgba_succ_iterator_union::recycle(const tgba* l, tgba_succ_iterator* left,
+				    const tgba* r, tgba_succ_iterator* right)
+  {
+    l->release_iter(left_);
+    left_ = left;
+    r->release_iter(right_);
+    right_ = right;
+  }
+
   tgba_succ_iterator_union::~tgba_succ_iterator_union()
   {
     delete left_;
@@ -278,45 +289,46 @@ namespace spot
     (void) global_automaton;
     const state_union* s = down_cast<const state_union*>(local_state);
     assert(s);
-    tgba_succ_iterator_union* res = 0;
     // Is it the initial state ?
+    tgba_succ_iterator* li;
+    tgba_succ_iterator* ri;
     if (!s->left() && !s->right())
       {
 	// Yes, create an iterator with both initial states.
 	state* left_init = left_->get_init_state();
 	state* right_init = right_->get_init_state();
-      tgba_succ_iterator* li = left_->succ_iter(left_init);
+	li = left_->succ_iter(left_init);
-      tgba_succ_iterator* ri = right_->succ_iter(right_init);
+	ri = right_->succ_iter(right_init);
-      res = new tgba_succ_iterator_union(li, ri, left_acc_missing_,
-					 right_acc_missing_,
-					 left_var_missing_,
-					 right_var_missing_);
 	left_init->destroy();
 	right_init->destroy();
       }
-    else
-    {
     // No, create an iterator based on the corresponding state
     // in the left or in the right automaton.
-      if (s->left())
+    else if (s->left())
       {
-        tgba_succ_iterator* li = left_->succ_iter(s->left());
+        li = left_->succ_iter(s->left());
-	res = new tgba_succ_iterator_union(li, 0, left_acc_missing_,
+	ri = nullptr;
-					   right_acc_missing_,
-					   left_var_missing_,
-					   right_var_missing_);
       }
     else
       {
-	tgba_succ_iterator* ri = right_->succ_iter(s->right());
+	li = nullptr;
-	res = new tgba_succ_iterator_union(0, ri, left_acc_missing_,
+	ri = right_->succ_iter(s->right());
+      }
+
+    if (iter_cache_)
+      {
+	tgba_succ_iterator_union* res =
+	  down_cast<tgba_succ_iterator_union*>(iter_cache_);
+	res->recycle(left_, li, right_, ri);
+	iter_cache_ = nullptr;
+	return res;
+      }
+    return new tgba_succ_iterator_union(li, ri,
+					left_acc_missing_,
 					right_acc_missing_,
 					left_var_missing_,
 					right_var_missing_);
   }
-    }
-    return res;
-  }
 
   bdd
   tgba_union::compute_support_conditions(const state* in) const

src/tgba/tgbaunion.hh

@@ -1,5 +1,5 @@
 // -*- coding: utf-8 -*-
-// Copyright (C) 2009, 2011, 2013 Laboratoire de Recherche et
+// Copyright (C) 2009, 2011, 2013, 2014 Laboratoire de Recherche et
 // Développement de l'Epita (LRDE).
 //
 // This file is part of Spot, a model checking library.
@@ -84,6 +84,9 @@ namespace spot
 			     bdd left_missing,
 			     bdd right_missing, bdd left_var, bdd right_var);
 
+    void recycle(const tgba* l, tgba_succ_iterator* left,
+		 const tgba* r, tgba_succ_iterator* right);
+
     virtual ~tgba_succ_iterator_union();
 
     // iteration

src/tgba/wdbacomp.cc

@@ -1,5 +1,5 @@
 // -*- coding: utf-8 -*-
-// Copyright (C) 2011, 2012, 2013 Laboratoire de Recherche et
+// Copyright (C) 2011, 2012, 2013, 2014 Laboratoire de Recherche et
 // Développement de l'Epita.
 //
 // This file is part of Spot, a model checking library.
@@ -95,6 +95,12 @@ namespace spot
       {
       }
 
+      void recycle(const tgba* a, tgba_succ_iterator* it)
+      {
+	a->release_iter(it_);
+	it_ = it;
+      }
+
       virtual
       ~tgba_wdba_comp_proxy_succ_iterator()
       {
@@ -197,9 +203,17 @@ namespace spot
 	assert(s);
 
 	const state* o = s->real_state();
-	tgba_succ_iterator* it = 0;
+	tgba_succ_iterator* it = nullptr;
 	if (o)
 	  it = a_->succ_iter(s->real_state(), global_state, global_automaton);
+	if (iter_cache_)
+	  {
+	    tgba_wdba_comp_proxy_succ_iterator* res =
+	      down_cast<tgba_wdba_comp_proxy_succ_iterator*>(iter_cache_);
+	    res->recycle(a_, it);
+	    iter_cache_ = nullptr;
+	    return res;
+	  }
 	return new tgba_wdba_comp_proxy_succ_iterator(it,
 						      the_acceptance_cond_);
       }

src/tgbaalgos/bfssteps.cc

@@ -1,4 +1,4 @@
-// Copyright (C) 2004  Laboratoire d'Informatique de Paris 6 (LIP6),
+// Copyright (C) 2004, 2014  Laboratoire d'Informatique de Paris 6 (LIP6),
 // département Systèmes Répartis Coopératifs (SRC), Université Pierre
 // et Marie Curie.
 //
@@ -88,7 +88,7 @@ namespace spot
 	      {
 		// Found it!
                 finalize(father, s, start, l);
-		delete i;
+		a_->release_iter(i);
 		return dest;
 	      }
 
@@ -100,7 +100,7 @@ namespace spot
 		father[dest] = s;
 	      }
 	  }
-	delete i;
+	a_->release_iter(i);
       }
     return 0;
   }

src/tgbaalgos/compsusp.cc

@@ -339,7 +339,8 @@ namespace spot
 		  else
 		    break;
 		}
-	      delete ri;
+	      if (ri)
+		right->release_iter(ri);
 	    }
 	}
       delete left;

src/tgbaalgos/cycles.cc

@@ -136,7 +136,7 @@ namespace spot
 	    // No more successors.
 	    bool f = cur.f;
 	    tagged_state v = cur.ts;
-	    delete cur.succ;
+	    aut_->release_iter(cur.succ);
 
 	    dfs_.pop_back();
 	    if (f)
@@ -158,7 +158,7 @@ namespace spot
     // returned false.
     while (!dfs_.empty())
       {
-	delete dfs_.back().succ;
+	aut_->release_iter(dfs_.back().succ);
 	dfs_.pop_back();
       }
 

src/tgbaalgos/dtbasat.cc

@@ -438,8 +438,7 @@ namespace spot
 
 	  dout << "(3) augmenting paths based on Cand[" << q1
 	       << "] and Ref[" << q1p << "]\n";
-	  tgba_succ_iterator* it = ref->succ_iter(d.int_to_state[q1p]);
+	  for (auto it: ref->succ(d.int_to_state[q1p]))
-	  for (it->first(); !it->done(); it->next())
 	    {
 	      const state* dps = it->current_state();
 	      int dp = d.state_to_int[dps];
@@ -469,7 +468,6 @@ namespace spot
 		    }
 		}
 	    }
-	  delete it;
 	}
 
       bdd all_acc = ref->all_acceptance_conditions();
@@ -502,9 +500,7 @@ namespace spot
 		    else
 		      pid1 = d.pathid_ref[p1];
 
-		    tgba_succ_iterator* it =
+		    for (auto it: ref->succ(d.int_to_state[q2p]))
-		      ref->succ_iter(d.int_to_state[q2p]);
-		    for (it->first(); !it->done(); it->next())
 		      {
 			const state* dps = it->current_state();
 			// Skip destinations not in the SCC.
@@ -567,7 +563,6 @@ namespace spot
 			      }
 			  }
 		      }
-		    delete it;
 		  }
 	    }
 	}
@@ -598,9 +593,7 @@ namespace spot
 		    else
 		      pid1 = d.pathid_cand[p1];
 
-		    tgba_succ_iterator* it =
+		    for (auto it: ref->succ(d.int_to_state[q2p]))
-		      ref->succ_iter(d.int_to_state[q2p]);
-		    for (it->first(); !it->done(); it->next())
 		      {
 			const state* dps = it->current_state();
 			// Skip destinations not in the SCC.
@@ -665,7 +658,6 @@ namespace spot
 			      }
 			  }
 		      }
-		    delete it;
 		  }
 	    }
 	}

src/tgbaalgos/dtgbasat.cc

@@ -582,8 +582,7 @@ namespace spot
 	  path p1(q1, q1p);
 	  int p1id = d.pathid[p1];
 
-	  tgba_succ_iterator* it = ref->succ_iter(d.int_to_state[q1p]);
+	  for (auto it: ref->succ(d.int_to_state[q1p]))
-	  for (it->first(); !it->done(); it->next())
 	    {
 	      const state* dps = it->current_state();
 	      int dp = d.state_to_int[dps];
@@ -612,7 +611,6 @@ namespace spot
 		    }
 		}
 	    }
-	  delete it;
 	}
 
       bdd all_acc = ref->all_acceptance_conditions();
@@ -645,10 +643,7 @@ namespace spot
 
 			  int pid = d.pathid[p];
 
-			  tgba_succ_iterator* it =
+			  for (auto it: ref->succ(d.int_to_state[q2p]))
-			    ref->succ_iter(d.int_to_state[q2p]);
-
-			  for (it->first(); !it->done(); it->next())
 			    {
 			      const state* dps = it->current_state();
 			      // Skip destinations not in the SCC.
@@ -836,7 +831,6 @@ namespace spot
 				    }
 				}
 			    }
-			  delete it;
 			}
 		  }
 	    }

src/tgbaalgos/gtec/gtec.cc

@@ -1,8 +1,9 @@
-// Copyright (C) 2008, 2011 Laboratoire de Recherche et Développement
+// -*- coding: utf-8 -*-
-// de l'Epita (LRDE).
+// Copyright (C) 2008, 2011, 2014 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),
+// Paris 6 (LIP6), département Systèmes Répartis Coopératifs (SRC),
-// Université Pierre et Marie Curie.
+// Université Pierre et Marie Curie.
 //
 // This file is part of Spot, a model checking library.
 //
@@ -135,7 +136,7 @@ namespace spot
 		to_remove.push(ecs_->aut->succ_iter(spi.first));
 	      }
 	  }
-	delete i;
+	ecs_->aut->release_iter(i);
 	if (to_remove.empty())
 	  break;
 	i = to_remove.top();
@@ -212,8 +213,7 @@ namespace spot
 		remove_component(curr);
 		ecs_->root.pop();
 	      }
-
+	    ecs_->aut->release_iter(succ);
-	    delete succ;
 	    // Do not destroy CURR: it is a key in H.
 	    continue;
 	  }
@@ -288,7 +288,7 @@ namespace spot
 	    // Release all iterators in TODO.
 	    while (!todo.empty())
 	      {
-		delete todo.top().second;
+		ecs_->aut->release_iter(todo.top().second);
 		todo.pop();
 		dec_depth();
 	      }
@@ -325,14 +325,13 @@ namespace spot
 					     couvreur99_check_shy* shy)
 	: s(s), n(n)
   {
-    tgba_succ_iterator* iter = shy->ecs_->aut->succ_iter(s);
+    for (auto iter: shy->ecs_->aut->succ(s))
-    for (iter->first(); !iter->done(); iter->next(), shy->inc_transitions())
       {
 	q.push_back(successor(iter->current_acceptance_conditions(),
 			      iter->current_state()));
 	shy->inc_depth();
+	shy->inc_transitions();
       }
-    delete iter;
   }
 
   couvreur99_check_shy::couvreur99_check_shy(const tgba* a,

src/tgbaalgos/gv04.cc

@@ -1,6 +1,6 @@
 // -*- coding: utf-8 -*-
-// Copyright (C) 2008, 2010, 2011, 2013 Laboratoire de recherche et
+// Copyright (C) 2008, 2010, 2011, 2013, 2014 Laboratoire de recherche
-// développement de l'Epita (LRDE).
+// et développement de l'Epita (LRDE).
 // Copyright (C) 2004, 2005 Laboratoire d'Informatique de Paris 6
 // (LIP6), département Systèmes Répartis Coopératifs (SRC), Université
 // Pierre et Marie Curie.
@@ -80,7 +80,7 @@ namespace spot
       ~gv04()
       {
 	for (stack_type::iterator i = stack.begin(); i != stack.end(); ++i)
-	  delete i->lasttr;
+	  a_->release_iter(i->lasttr);
 	hash_type::const_iterator s = h.begin();
 	while (s != h.end())
 	  {
@@ -203,7 +203,7 @@ namespace spot
 	    assert(static_cast<unsigned int>(top + 1) == stack.size());
 	    for (int i = top; i >= dftop; --i)
 	      {
-		delete stack[i].lasttr;
+		a_->release_iter(stack[i].lasttr);
 		stack.pop_back();
 		dec_depth();
 	      }

src/tgbaalgos/isweakscc.cc

@@ -1,5 +1,6 @@
-// Copyright (C) 2012, 2013 Laboratoire de Recherche et Developpement
+// -*- coding: utf-8 -*-
-// de l'Epita (LRDE).
+// Copyright (C) 2012, 2013, 2014 Laboratoire de Recherche et
+// Developpement de l'Epita (LRDE).
 //
 // This file is part of Spot, a model checking library.
 //
@@ -96,12 +97,10 @@ namespace spot
     if (!aut)
       return false;
 
-    const std::list<const spot::state*> states = map.states_of(scc);
+    for (auto ss: map.states_of(scc))
-    std::list<const spot::state*>::const_iterator it;
-    for (it = states.begin(); it != states.end(); ++it)
       {
 	const state_explicit_formula* s =
-	  down_cast<const state_explicit_formula*>(*it);
+	  down_cast<const state_explicit_formula*>(ss);
 	assert(s);
 	if (aut->get_label(s)->is_syntactic_persistence())
 	  return true;
@@ -117,12 +116,10 @@ namespace spot
     if (!aut)
       return false;
 
-    const std::list<const spot::state*> states = map.states_of(scc);
+    for (auto ss: map.states_of(scc))
-    std::list<const spot::state*>::const_iterator it;
-    for (it = states.begin(); it != states.end(); ++it)
       {
 	const state_explicit_formula* s =
-	  down_cast<const state_explicit_formula*>(*it);
+	  down_cast<const state_explicit_formula*>(ss);
 	assert(s);
 	if (aut->get_label(s)->is_syntactic_guarantee())
 	  return true;
@@ -134,18 +131,15 @@ namespace spot
   is_complete_scc(scc_map& map, unsigned scc)
   {
     const spot::tgba *a = map.get_aut();
-    const std::list<const spot::state*> states = map.states_of(scc);
+    for (auto s: map.states_of(scc))
-    std::list<const spot::state*>::const_iterator it;
-    for (it = states.begin(); it != states.end(); ++it)
       {
-	const state *s = *it;
 	tgba_succ_iterator* it = a->succ_iter(s);
 	it->first();
 
 	// If a state has no successors, the SCC is not complete.
 	if (it->done())
 	  {
-	    delete it;
+	    a->release_iter(it);
 	    return false;
 	  }
 
@@ -163,7 +157,7 @@ namespace spot
 	    it->next();
 	  }
 	while (!it->done());
-	delete it;
+	a->release_iter(it);
 
 	if (sumall != bddtrue)
 	  return false;

src/tgbaalgos/lbtt.cc

@@ -1,9 +1,9 @@
 // -*- coding: utf-8 -*-
-// Copyright (C) 2011, 2012, 2013 Laboratoire de Recherche et
+// Copyright (C) 2011, 2012, 2013, 2014 Laboratoire de Recherche et
 // Développement de l'Epita (LRDE).
-// Copyright (C) 2003, 2004, 2005  Laboratoire d'Informatique de Paris 6 (LIP6),
+// Copyright (C) 2003, 2004, 2005 Laboratoire d'Informatique de Paris
-// département Systèmes Répartis Coopératifs (SRC), Université Pierre
+// 6 (LIP6), département Systèmes Répartis Coopératifs (SRC),
-// et Marie Curie.
+// Université Pierre et Marie Curie.
 //
 // This file is part of Spot, a model checking library.
 //
@@ -104,7 +104,7 @@ namespace spot
 	it->first();
 	bool accepting =
 	  !it->done() && it->current_acceptance_conditions() == all_acc_conds_;
-	delete it;
+	aut_->release_iter(it);
 	return accepting;
       }
 

src/tgbaalgos/ltl2tgba_fm.cc

@@ -110,7 +110,7 @@ namespace spot
     {
     public:
       ratexp_to_dfa(translate_dict& dict);
-      tgba_succ_iterator* succ(const formula* f);
+      std::pair<tgba_explicit_formula*, const state*> succ(const formula* f);
       const formula* get_label(const formula* f, const state* s) const;
       ~ratexp_to_dfa();
 
@@ -1133,7 +1133,7 @@ namespace spot
     }
 
     // FIXME: use the new tgba::succ() interface
-    tgba_succ_iterator*
+    std::pair<tgba_explicit_formula*, const state*>
     ratexp_to_dfa::succ(const formula* f)
     {
       f2a_t::const_iterator it = f2a_.find(f);
@@ -1145,13 +1145,11 @@ namespace spot
 
       // If a is nul, f has an empty language.
       if (!a)
-	return 0;
+	return {nullptr, nullptr};
 
       assert(a->has_state(f));
       // This won't create a new state.
-      const state* s = a->add_state(f);
+      return {a, a->add_state(f)};
-
-      return a->succ_iter(s);
     }
 
     const formula*
@@ -1364,12 +1362,11 @@ namespace spot
 	    {
 	      // rat_seen_ = true;
 	      const formula* f = node->child();
-	      tgba_succ_iterator* i = dict_.transdfa.succ(f);
+	      auto p = dict_.transdfa.succ(f);
 	      res_ = bddfalse;
-
+	      if (!p.first)
-	      if (!i)
 		break;
-	      for (i->first(); !i->done(); i->next())
+	      for (auto i: p.first->succ(p.second))
 		{
 		  bdd label = i->current_condition();
 		  state* s = i->current_state();
@@ -1391,7 +1388,6 @@ namespace spot
 		      res_ |= label & bdd_ithvar(x);
 		    }
 		}
-	      delete i;
 	    }
 	    break;
 

src/tgbaalgos/magic.cc

@@ -1,6 +1,6 @@
 // -*- coding: utf-8 -*-
-// Copyright (C) 2011, 2013 Laboratoire de recherche et développement de
+// Copyright (C) 2011, 2013, 2014 Laboratoire de recherche et
-// l'Epita (LRDE).
+// développement de l'Epita (LRDE).
 // Copyright (C) 2004, 2005  Laboratoire d'Informatique de Paris 6 (LIP6),
 // département Systèmes Répartis Coopératifs (SRC), Université Pierre
 // et Marie Curie.
@@ -68,13 +68,13 @@ namespace spot
         while (!st_blue.empty())
           {
             h.pop_notify(st_blue.front().s);
-            delete st_blue.front().it;
+            a_->release_iter(st_blue.front().it);
             st_blue.pop_front();
           }
         while (!st_red.empty())
           {
             h.pop_notify(st_red.front().s);
-            delete st_red.front().it;
+            a_->release_iter(st_red.front().it);
             st_red.pop_front();
           }
       }
@@ -159,7 +159,7 @@ namespace spot
       void pop(stack_type& st)
       {
         dec_depth();
-        delete st.front().it;
+	a_->release_iter(st.front().it);
         st.pop_front();
       }
 

src/tgbaalgos/ndfs_result.hxx

@@ -1,6 +1,6 @@
 // -*- coding: utf-8 -*-
-// Copyright (C) 2011, 2013 Laboratoire de recherche et développement de
+// Copyright (C) 2011, 2013, 2014 Laboratoire de recherche et
-// l'Epita (LRDE).
+// développement de l'Epita (LRDE).
 // Copyright (C) 2004, 2005, 2006  Laboratoire d'Informatique de Paris 6 (LIP6),
 // département Systèmes Répartis Coopératifs (SRC), Université Pierre
 // et Marie Curie.
@@ -230,11 +230,11 @@ namespace spot
     typedef std::unordered_set<const state*,
 			       state_ptr_hash, state_ptr_equal> state_set;
 
-    void clean(stack_type& st1, state_set& seen, state_set& dead)
+    void clean(const tgba* a, stack_type& st1, state_set& seen, state_set& dead)
     {
       while (!st1.empty())
 	{
-	  delete st1.front().it;
+	  a->release_iter(st1.front().it);
 	  st1.pop_front();
 	}
       for (state_set::iterator i = seen.begin(); i != seen.end();)
@@ -309,7 +309,7 @@ namespace spot
                           covered_acc |= acc;
                           if (covered_acc == a_->all_acceptance_conditions())
                             {
-                              clean(st1, seen, dead);
+                              clean(a_, st1, seen, dead);
                               s_prime->destroy();
                               return true;
                             }
@@ -334,7 +334,7 @@ namespace spot
               ndfsr_trace << "  all the successors have been visited"
                           << std::endl;
               stack_item f_dest(f);
-              delete st1.front().it;
+              a_->release_iter(st1.front().it);
               st1.pop_front();
               if (!st1.empty() && (f_dest.acc & covered_acc) != f_dest.acc)
                 {
@@ -351,7 +351,7 @@ namespace spot
                       covered_acc |= f_dest.acc;
                       if (covered_acc == a_->all_acceptance_conditions())
                         {
-                          clean(st1, seen, dead);
+                          clean(a_, st1, seen, dead);
                           return true;
                         }
                     }
@@ -364,7 +364,7 @@ namespace spot
             }
         }
 
-      clean(st1, seen, dead);
+      clean(a_, st1, seen, dead);
       return false;
     }
 

src/tgbaalgos/neverclaim.cc

@@ -1,7 +1,8 @@
-// Copyright (C) 2009, 2011, 2012 Laboratoire de Recherche et
+// -*- coding: utf-8 -*-
-// Développement de l'Epita (LRDE).
+// Copyright (C) 2009, 2011, 2012, 2014 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
+// département Systèmes Répartis Coopératifs (SRC), Université Pierre
 // et Marie Curie.
 //
 // This file is part of Spot, a model checking library.
@@ -88,7 +89,7 @@ namespace spot
 	it->first();
 	bool accepting =
 	  !it->done() && it->current_acceptance_conditions() == all_acc_conds_;
-	delete it;
+	aut_->release_iter(it);
 	return accepting;
       }
 
@@ -123,7 +124,7 @@ namespace spot
 		      label = "accept_all";
 		    current->destroy();
 		  }
-		delete it;
+		aut_->release_iter(it);
 	      }
 	    else
 	      label = "T0_S" + ns;
@@ -149,7 +150,7 @@ namespace spot
 	  }
 	else
 	  {
-	    state* current =it->current_state();
+	    state* current = it->current_state();
 	    if (state_is_accepting(s)
 		&& it->current_condition() == bddtrue
 		&& s->compare(init_) != 0
@@ -167,7 +168,7 @@ namespace spot
 	      }
 	    current->destroy();
 	  }
-	  delete it;
+	aut_->release_iter(it);
       }
 
       void

src/tgbaalgos/reachiter.cc

@@ -1,7 +1,8 @@
-// Copyright (C) 2009, 2011, 2013 Laboratoire de Recherche et
+// -*- coding: utf-8 -*-
-// Développement de l'Epita (LRDE).
+// Copyright (C) 2009, 2011, 2013, 2014 Laboratoire de Recherche et
+// Développement de l'Epita (LRDE).
 // Copyright (C) 2003, 2004 Laboratoire d'Informatique de Paris 6 (LIP6),
-// département Systèmes Répartis Coopératifs (SRC), Université Pierre
+// département Systèmes Répartis Coopératifs (SRC), Université Pierre
 // et Marie Curie.
 //
 // This file is part of Spot, a model checking library.
@@ -81,7 +82,7 @@ namespace spot
 		current->destroy();
 	      }
 	  }
-	delete si;
+	aut_->release_iter(si);
       }
     end();
   }
@@ -174,7 +175,7 @@ namespace spot
   void
   tgba_reachable_iterator_depth_first::pop()
   {
-    delete todo.back().it;
+    aut_->release_iter(todo.back().it);
     todo.pop_back();
     if (!todo.empty())
       todo.back().it->next();

src/tgbaalgos/replayrun.cc

@@ -1,6 +1,6 @@
 // -*- coding: utf-8 -*-
-// Copyright (C) 2011, 2013 Laboratoire de Recherche et Développement
+// Copyright (C) 2011, 2013, 2014 Laboratoire de Recherche et
-// de l'Epita (LRDE).
+// 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.
@@ -189,7 +189,7 @@ namespace spot
 		    s2->destroy();
 		  }
 	      }
-	    delete j;
+	    a->release_iter(j);
 	    s->destroy();
 	    return false;
 	  }
@@ -211,7 +211,7 @@ namespace spot
 	    bdd_print_accset(os, a->get_dict(), acc);
 	    os << std::endl;
 	  }
-	delete j;
+	a->release_iter(j);
 
 	// Sum acceptance conditions.
 	//

src/tgbaalgos/safety.cc

@@ -60,7 +60,7 @@ namespace spot
 	it->next();
 	result = (!dest->compare(s)) && it->done() && (cond == bddtrue);
 	dest->destroy();
-	delete it;
+	aut->release_iter(it);
       }
 
     // Free the scc_map if we created it.

src/tgbaalgos/scc.cc

@@ -1,6 +1,6 @@
 // -*- coding: utf-8 -*-
-// Copyright (C) 2008, 2009, 2011, 2012, 2013 Laboratoire de Recherche
+// Copyright (C) 2008, 2009, 2011, 2012, 2013, 2014 Laboratoire de
-// et Développement de l'Epita.
+// Recherche et Développement de l'Epita.
 //
 // This file is part of Spot, a model checking library.
 //
@@ -199,7 +199,7 @@ namespace spot
 		  root_.front().succ.insert(std::make_pair(num, cond));
 	      }
 
-	    delete succ;
+	    aut_->release_iter(succ);
 	    // Do not destroy CURR: it is a key in H.
 	    continue;
 	  }

src/tgbaalgos/se05.cc

@@ -1,6 +1,6 @@
 // -*- coding: utf-8 -*-
-// Copyright (C) 2011, 2013 Laboratoire de Recherche et Developpement de
+// Copyright (C) 2011, 2013, 2014 Laboratoire de Recherche et
-// l'Epita (LRDE).
+// Développement de l'Epita (LRDE).
 // Copyright (C) 2004, 2005  Laboratoire d'Informatique de Paris 6 (LIP6),
 // département Systèmes Répartis Coopératifs (SRC), Université Pierre
 // et Marie Curie.
@@ -68,13 +68,13 @@ namespace spot
         while (!st_blue.empty())
           {
             h.pop_notify(st_blue.front().s);
-            delete st_blue.front().it;
+            a_->release_iter(st_blue.front().it);
             st_blue.pop_front();
           }
         while (!st_red.empty())
           {
             h.pop_notify(st_red.front().s);
-            delete st_red.front().it;
+            a_->release_iter(st_red.front().it);
             st_red.pop_front();
           }
       }
@@ -159,7 +159,7 @@ namespace spot
       void pop(stack_type& st)
       {
         dec_depth();
-        delete st.front().it;
+        a_->release_iter(st.front().it);
         st.pop_front();
       }
 

src/tgbaalgos/simulation.cc

@@ -335,14 +335,12 @@ namespace spot
 	    // the acceptance of the destination state on its incoming
 	    // arcs (which now become outgoing args after
 	    // transposition).
-	    tgba_succ_iterator* it = out_->succ_iter(out_s);
+	    for (auto it: out_->succ(out_s))
-	    it->first();
-	    if (!it->done())
 	      {
 		bdd acc = ac_.complement(it->current_acceptance_conditions());
 		t->acceptance_conditions = acc;
+		break;
 	      }
-	    delete it;
 	  }
       }
 

src/tgbaalgos/tau03.cc

@@ -68,13 +68,13 @@ namespace spot
         while (!st_blue.empty())
           {
             h.pop_notify(st_blue.front().s);
-            delete st_blue.front().it;
+            a_->release_iter(st_blue.front().it);
             st_blue.pop_front();
           }
         while (!st_red.empty())
           {
             h.pop_notify(st_red.front().s);
-            delete st_red.front().it;
+            a_->release_iter(st_red.front().it);
             st_red.pop_front();
           }
       }
@@ -133,7 +133,7 @@ namespace spot
       void pop(stack_type& st)
       {
         dec_depth();
-        delete st.front().it;
+        a_->release_iter(st.front().it);
         st.pop_front();
       }
 

src/tgbaalgos/tau03opt.cc

@@ -1,6 +1,6 @@
 // -*- coding: utf-8 -*-
-// Copyright (C) 2011, 2013 Laboratoire de Recherche et Developpement de
+// Copyright (C) 2011, 2013, 2014 Laboratoire de Recherche et
-// l'Epita (LRDE).
+// Développement de l'Epita (LRDE).
 // Copyright (C) 2004, 2005  Laboratoire d'Informatique de Paris 6 (LIP6),
 // département Systèmes Répartis Coopératifs (SRC), Université Pierre
 // et Marie Curie.
@@ -93,13 +93,13 @@ namespace spot
         while (!st_blue.empty())
           {
             h.pop_notify(st_blue.front().s);
-            delete st_blue.front().it;
+            a_->release_iter(st_blue.front().it);
             st_blue.pop_front();
           }
         while (!st_red.empty())
           {
             h.pop_notify(st_red.front().s);
-            delete st_red.front().it;
+            a_->release_iter(st_red.front().it);
             st_red.pop_front();
           }
       }
@@ -158,7 +158,7 @@ namespace spot
       void pop(stack_type& st)
       {
         dec_depth();
-        delete st.front().it;
+        a_->release_iter(st.front().it);
         st.pop_front();
       }