diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 8d02e2b387c..20ce45ee287 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,7 @@
+2004-06-20  Zdenek Dvorak  <rakdver@atrey.karlin.mff.cuni.cz>
+
+	* tree-ssa-pre.c (compute_antic): Keep BB_VISITED flag zeroed.
+
 2004-06-20  Richard Henderson  <rth@redhat.com>
 
 	* stmt.c (warn_if_unused_value): Add locus argument.
diff --git a/gcc/tree-ssa-pre.c b/gcc/tree-ssa-pre.c
index 7c0aeb7dca3..6fbb37a6884 100644
--- a/gcc/tree-ssa-pre.c
+++ b/gcc/tree-ssa-pre.c
@@ -1286,7 +1286,8 @@ compute_antic (void)
   FOR_ALL_BB (bb)
     {
       ANTIC_IN (bb) = set_new (true);
-      bb->flags &= ~BB_VISITED;
+      if (bb->flags & BB_VISITED)
+	abort ();
     }
 
   while (changed)
@@ -1295,6 +1296,10 @@ compute_antic (void)
       changed = false;
       changed = compute_antic_aux (EXIT_BLOCK_PTR);
     }
+  FOR_ALL_BB (bb)
+    {
+      bb->flags &= ~BB_VISITED;
+    }
   if (num_iterations > 2 && dump_file && (dump_flags & TDF_STATS))
     fprintf (dump_file, "compute_antic required %d iterations\n", num_iterations);
 }