diff --git a/usr.bin/yacc/skeleton.c b/usr.bin/yacc/skeleton.c
index 0dc2e2e50ac2..a35981dc7908 100644
--- a/usr.bin/yacc/skeleton.c
+++ b/usr.bin/yacc/skeleton.c
@@ -60,7 +60,9 @@ char *banner[] =
     "#define YYBYACC 1",
     "#define YYMAJOR 1",
     "#define YYMINOR 9",
-    "#define yyclearin (yychar=(-1))",
+    "#define YYLEX yylex()",
+    "#define YYEMPTY -1",
+    "#define yyclearin (yychar=(YYEMPTY))",
     "#define yyerrok (yyerrflag=0)",
     "#define YYRECOVERING (yyerrflag!=0)",
     "/* cfront 1.2 defines \"c_plusplus\" instead of \"__cplusplus\" */",