#define optional_argument 2
#if defined (__STDC__) && __STDC__
-#ifdef __GNU_LIBRARY__
+/* HAVE_DECL_* is a three-state macro: undefined, 0 or 1. If it is
+ undefined, we haven't run the autoconf check so provide the
+ declaration without arguments. If it is 0, we checked and failed
+ to find the declaration so provide a fully prototyped one. If it
+ is 1, we found it so don't provide any declaration at all. */
+#if defined (__GNU_LIBRARY__) || (defined (HAVE_DECL_GETOPT) && !HAVE_DECL_GETOPT)
/* Many other libraries have conflicting prototypes for getopt, with
differences in the consts, in stdlib.h. To avoid compilation
errors, only prototype getopt for the GNU C library. */
extern int getopt (int argc, char *const *argv, const char *shortopts);
#else /* not __GNU_LIBRARY__ */
+# if !defined (HAVE_DECL_GETOPT)
extern int getopt ();
+# endif
#endif /* __GNU_LIBRARY__ */
extern int getopt_long (int argc, char *const *argv, const char *shortopts,
const struct option *longopts, int *longind);