1 files changed, 1 insertions, 0 deletions

diff --git a/pc.y b/pc.y
index 98c0bdc..23b3b24 100644
--- a/pc.y
+++ b/pc.y
@@ -122,6 +122,7 @@ program
 io_list
 	:IO
 	|io_list ',' IO
+	| /*empty*/
 ;
 
 id_list