Silence parser generator output.
diff --git a/Parser/firstsets.c b/Parser/firstsets.c
index d6c4084..fcd9ffd 100644
--- a/Parser/firstsets.c
+++ b/Parser/firstsets.c
@@ -15,8 +15,9 @@
 {
 	int i;
 	dfa *d;
-	
-	printf("Adding FIRST sets ...\n");
+
+	if (Py_DebugFlag)
+		printf("Adding FIRST sets ...\n");
 	for (i = 0; i < g->g_ndfas; i++) {
 		d = &g->g_dfa[i];
 		if (d->d_first == NULL)