diff -Nrup a/configure b/configure
--- a/configure 2019-12-19 22:20:13.297314380 -0700
+++ b/configure 2019-12-19 22:34:40.901669132 -0700
@@ -759,6 +759,7 @@ cat > conftest.$ac_ext <<EOF
#line 760 "configure"
#include "confdefs.h"
`cat $LEX_OUTPUT_ROOT.c`
+extern __attribute__ ((used)) int yywrap ( void );
int main() {
; return 0; }