1 files changed, 4 insertions, 0 deletions
diff --git a/x2p/a2p.h b/x2p/a2p.h
index 2db5f36ebc..80530469ed 100644
--- a/x2p/a2p.h
+++ b/x2p/a2p.h
@@ -412,6 +412,10 @@ EXT int debug INIT(0);
 EXT int dlevel INIT(0);
 #define YYDEBUG 1
 extern int yydebug;
+#else
+# ifndef YYDEBUG
+#  define YYDEBUG 0
+# endif
 #endif
 
 EXT STR *freestrroot INIT(Nullstr);