diff --git a/parse.yacc b/parse.yacc
index d24b3f0dc..4622be1a4 100644
--- a/parse.yacc
+++ b/parse.yacc
@@ -59,6 +59,7 @@ static char rcsid[] = "$Id$";
 
 extern int sudolineno, parse_error;
 int errorlineno = -1;
+int clearaliases = 1;
 
 /*
  * Alias types