build BUGFIX fix BSD builds, again, and cleanup
- just define _GNU_SOURCE and include sys/cdefs.h this gets everything
set the right way (no need to define _POSIX_C_SOURCE, etc).
- BSD requires more includes to get to sockaddr and AF_*
diff --git a/src/xpath.c b/src/xpath.c
index 5b558f1..0a65830 100644
--- a/src/xpath.c
+++ b/src/xpath.c
@@ -11,11 +11,8 @@
*
* https://opensource.org/licenses/BSD-3-Clause
*/
-#define _GNU_SOURCE
-#define _POSIX_C_SOURCE 200809L /* strdup, strndup */
-
-/* needed by libmath functions isfinite(), isinf(), isnan(), signbit(), ... */
-#define _ISOC99_SOURCE
+#define _GNU_SOURCE /* asprintf, strdup */
+#include <sys/cdefs.h>
#include "xpath.h"