Running ltl2tgba -R1q -R1t -N would degeneralize before and

after the simulation-reduction.

Report from Tomáš Babiak <xbabiak@fi.muni.cz>.

* src/tgbaalgos/neverclaim.hh (never_claim_reachable): Take
a tgba as input.
* src/tgbaalgos/neverclaim.cc (never_claim_bfs): Call
state_is_accepting() only if this tgba turns out to be
a tgba_sba_proxy.  Otherwise check the acceptance of one
outgoing transition as we do in dotty_bfs since 2011-03-05.
* src/tgbatest/ltl2tgba.cc: Do not redegeneralize before
calling never_claim_reachable() if we know the automaton is
degeneralized already.
* src/tgbatest/ltl2tgba.test: Add a test case.

src/tgbaalgos/neverclaim.hh

@@ -1,4 +1,4 @@
-// Copyright (C) 2009 Laboratoire de Recherche et Développement
+// Copyright (C) 2009, 2011 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
@@ -34,13 +34,16 @@ namespace spot
   /// \ingroup tgba_io
   ///
   /// \param os The output stream to print on.
-  /// \param g The degeneralized automaton to output.
+  /// \param g The (state-based degeneralized) automaton to output.
+  ///          There should be only one acceptance condition, and
+  ///          all the transitions of a state should be either all accepting
+  ///          or all unaccepting.
   /// \param f The (optional) formula associated to the automaton.  If given
   ///          it will be output as a comment.
   /// \param comments Whether to comment each state of the never clause
   ///          with the label of the \a g automaton.
   std::ostream& never_claim_reachable(std::ostream& os,
-				      const tgba_sba_proxy* g,
+				      const tgba* g,
 				      const ltl::formula* f = 0,
 				      bool comments = false);
 }