diff --git a/ChangeLog b/ChangeLog
index 42586c1ff..4e86ae5d5 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2004-12-10  Alexandre Duret-Lutz  <adl@src.lip6.fr>
+
+	* src/tgbaalgos/randomgraph.cc (random_graph): Do not use the
+	pointer of the state created as keys in sets; otherwise the graph
+	created depends on the memory layout.
+
 2004-12-09  Alexandre Duret-Lutz  <adl@src.lip6.fr>
 
 	* src/tgba/tgbaexplicit.cc (tgba_explicit::create_transition):
diff --git a/src/tgbaalgos/randomgraph.cc b/src/tgbaalgos/randomgraph.cc
index e60583211..bf4904e8c 100644
--- a/src/tgbaalgos/randomgraph.cc
+++ b/src/tgbaalgos/randomgraph.cc
@@ -28,7 +28,6 @@
 #include <list>
 #include <set>
 #include <iterator>
-#include "misc/hash.hh"
 
 namespace spot
 {
@@ -123,15 +122,22 @@ namespace spot
 
 
     // Using Sgi::hash_set instead of std::set for these sets is 3
-    // times slower (tested on a 50000 nodes example).
-    typedef std::set<tgba_explicit::state*> node_set;
+    // times slower (tested on a 50000 nodes example).  Use an int
+    // (the index into states[]), not the tgba_explicit::state*
+    // directly, because the later would yield different graph
+    // depending on the memory layout.
+    typedef std::set<int> node_set;
     node_set nodes_to_process;
     node_set unreachable_nodes;
 
-    nodes_to_process.insert(states[0] = res->add_state(st(0)));
+    states[0] = res->add_state(st(0));
+    nodes_to_process.insert(0);
 
     for (int i = 1; i < n; ++i)
-      unreachable_nodes.insert(states[i] = res->add_state(st(i)));
+      {
+	states[i] = res->add_state(st(i));
+	unreachable_nodes.insert(i);
+      }
 
     // We want to connect each node to a number of successors between
     // 1 and n (with probability d).  This follow
@@ -139,7 +145,7 @@ namespace spot
 
     while (!nodes_to_process.empty())
       {
-	tgba_explicit::state* src = *nodes_to_process.begin();
+	tgba_explicit::state* src = states[*nodes_to_process.begin()];
 	nodes_to_process.erase(nodes_to_process.begin());
 
 	// Choose a random number of successors (at least one), using
@@ -163,7 +169,7 @@ namespace spot
 		std::advance(i, index);
 
 		// Link it from src.
-		random_labels(res, src, *i, props, props_n, t, accs, a);
+		random_labels(res, src, states[*i], props, props_n, t, accs, a);
 
 		nodes_to_process.insert(*i);
 		unreachable_nodes.erase(i);
@@ -182,10 +188,10 @@ namespace spot
 
 		random_labels(res, src, dest, props, props_n, t, accs, a);
 
-		node_set::iterator j = unreachable_nodes.find(dest);
+		node_set::iterator j = unreachable_nodes.find(index);
 		if (j != unreachable_nodes.end())
 		  {
-		    nodes_to_process.insert(dest);
+		    nodes_to_process.insert(index);
 		    unreachable_nodes.erase(j);
 		    saw_unreachable = true;
 		  }