--- ./sql/sql_yacc.yy_orig	2020-03-17 07:19:23 +0000
+++ ./sql/sql_yacc.yy	2020-03-17 07:19:46 +0000
@@ -269,7 +269,7 @@
      The result will be in the process stderr (var/log/master.err)
    */
 
-  extern int yydebug;
+  static int yydebug;
   yydebug= 1;
 }
 #endif