+/* Check that the 'socklen_t' type is defined. */
+socklen_t t1;
+
+/* Check that the 'size_t' and 'ssize_t' types are defined. */
+size_t t2;
+ssize_t t3;
+
+/* Check that 'struct iovec' is defined. */
+struct iovec io;
+
+/* Check that a minimal set of 'struct msghdr' is defined. */
+struct msghdr msg;
+