diff --git a/ext/sockets/conversions.c b/ext/sockets/conversions.c
index ecf3fb47b508d..1b7124cae5f34 100644
--- a/ext/sockets/conversions.c
+++ b/ext/sockets/conversions.c
@@ -1,3 +1,7 @@
+#ifdef __sun
+/* to enable 'new' ancillary data layout instead */
+# define _XPG4_2
+#endif
 #include "sockaddr_conv.h"
 #include "conversions.h"
 #include "sendrecvmsg.h" /* for ancillary registry */
diff --git a/ext/sockets/sendrecvmsg.c b/ext/sockets/sendrecvmsg.c
index 906e6b81007b5..f7326986cb22d 100644
--- a/ext/sockets/sendrecvmsg.c
+++ b/ext/sockets/sendrecvmsg.c
@@ -14,6 +14,10 @@
    +----------------------------------------------------------------------+
  */
 
+#ifdef __sun
+/* to enable 'new' ancillary data layout instead */
+# define _XPG4_2
+#endif
 #include <php.h>
 #include "php_sockets.h"
 #include "sendrecvmsg.h"