diff --git a/src/aclyacc.y b/src/aclyacc.y
index 60001b6..78d0955 100644
--- a/src/aclyacc.y
+++ b/src/aclyacc.y
@@ -3,6 +3,9 @@
 #include "acl2.h"
 #include <stdio.h> /* XXX REMOVE */
 
+int yylex(void);
+void yyerror(const char *);
+
 /* XXX remove */
 unsigned char fmt_buf[32];
 unsigned char fmt_buf2[32];