diff --git a/functions/frontier.c b/functions/frontier.c
index 9945134b2a736f24fd45d5e364b4ebb744288ac2..d52f0c82972f6430a10e43cedd4377b7058a03a7 100644
--- a/functions/frontier.c
+++ b/functions/frontier.c
@@ -295,12 +295,13 @@ void detect_potential_deadlock(function * fun)
 	bitmap_initialize( &test,  &bitmap_default_obstack);
 	if(bitmap_intersect_p(&ipdf_set, &mpi_set)){
 		printf("! WARNING ! \n");
-		bitmap_print( stdout, &ipdf_set, "Potential problems blocks : ", "\n\n" ) ;
+		bitmap_set_pdf_union(mpi_set, pfrontiers, &test, fun); 
+		bitmap_print( stdout, &test, "Potential problems blocks : ", "\n\n" ) ;
+		issue_warnings(test,fun);
 	}else
 	{
 		printf("No potential deadlock detected\n");
 	}
-	issue_warnings(ipdf_set,fun);
         free_dominance_info(fun, CDI_POST_DOMINATORS);
 }