incompatible with our later declaration, perhaps by using const
attributes. So we hide the declaration in errno.h (if any) using a
macro. */
+#define sys_nerr sys_nerr__
#define sys_errlist sys_errlist__
#endif
#include <errno.h>
#ifdef HAVE_SYS_ERRLIST
+#undef sys_nerr
#undef sys_errlist
#endif