form_wrap.h in ncursesw-1.4.0.0 vs form_wrap.h in ncursesw-1.4.1

@@ -24,9 +24,11 @@
  */
 
 #if !defined(FORM_HH) && (defined(HAVE_FORM_H) || defined(HAVE_NCURSESW_FORM_H))
 #define FORM_HH
 
+# define _XOPEN_SOURCE_EXTENDED
+
 #ifdef HAVE_FORM_H
 #include <form.h>
 #else
 #include <ncursesw/form.h>
 #endif