Fix detection of the last iteration of minimize_dfa().

* src/tgbaalgos/minimize.cc (minimize_dfa): Fix detection of the
last iteration.  An extra iteration case could be missed in case
where a split generates only singletons, and yet predecessor
classes need to be refined.

AUTHORS

 Have contributed to Spot:
 
+Ala-Eddine Ben-Salem
 Alexandre Duret-Lutz
 Damien Lefortier
 Denis Poitrenaud

ChangeLog

+2012-01-05  Ala-Eddine Ben-Salem  <ala@lrde.epita.fr>
+
+	Fix detection of the last iteration of minimize_dfa().
+
+	* src/tgbaalgos/minimize.cc (minimize_dfa): Fix detection of the
+	last iteration.  An extra iteration case could be missed in case
+	where a split generates only singletons, and yet predecessor
+	classes need to be refined.
+
 2012-01-05  Alexandre Duret-Lutz  <adl@lrde.epita.fr>
 
 	Fix computation of length of LTL formulas.

NEWS

@@ -3,6 +3,10 @@ New in spot 0.8.1a:
   * Bug fixes:
     - spot::ltl::length() forgot to count the '&' and '|' operators
       in an LTL formula.
+    - minimize_dfa() could produce incorrect automata, but it's not
+      clear whether this could have had an inpact on WDBA minimization
+      (the worse case is that some TGBA would not have been minimized
+      when they could).
 
 New in spot 0.8.1:
 

src/tgbaalgos/minimize.cc

-// Copyright (C) 2010, 2011 Laboratoire de Recherche et Développement
+// Copyright (C) 2010, 2011, 2012 Laboratoire de Recherche et Développement
 // de l'Epita (LRDE).
 //
 // This file is part of Spot, a model checking library.
@@ -425,6 +425,7 @@ namespace spot
 	      }
 	    else
 	      {
+		did_split = true;
 		for (; bsi != bdd_map.end(); ++bsi)
 		  {
 		    hash_set* set = bsi->second;
@@ -457,7 +458,6 @@ namespace spot
 		      }
 		    else
 		      {
-			did_split = true;
 			trace << "set " << format_hash_set(set, det_a)
 			      << " should be processed further" << std::endl;
 			next_run.push_back(set);