use (void) for empty parameter lists to suppress compiler wanings

diff --git a/lib/graph/parser.y b/lib/graph/parser.y
index 0f9ebcbbea9c71a892118f01833abe5d5dbe17fe..4bb215e7b4ccfa347914b6db8cfeb6d082a94be2 100644 (file)
--- a/lib/graph/parser.y
+++ b/lib/graph/parser.y
@@ -34,7 +34,7 @@ static objstack_t     *SP;
 static Agraph_t                *Gstack[32];
 static int                     GSP;
 
-static void subgraph_warn ()
+static void subgraph_warn (void)
 {
     agerr (AGWARN, "The use of \"subgraph %s\", line %d, without a body is deprecated.\n",
        G->name, aglinenumber());