+#include "signature.h"
+
+/* The following may be macros without underlying functions, so only
+ check signature if they are not macros. */
+#ifndef FD_CLR
+SIGNATURE_CHECK (FD_CLR, void, (int, fd_set *));
+#endif
+#ifndef FD_ISSET
+SIGNATURE_CHECK (FD_ISSET, void, (int, fd_set *));
+#endif
+#ifndef FD_SET
+SIGNATURE_CHECK (FD_SET, int, (int, fd_set *));
+#endif
+#ifndef FD_ZERO
+SIGNATURE_CHECK (FD_ZERO, void, (fd_set *));
+#endif
+
+/* Check that the 'struct timeval' type is defined. */
+struct timeval a;
+
+/* Check that &a.tv_sec is a 'time_t *', ignoring signedness issues. */
+typedef int verify_tv_sec_type[sizeof (a.tv_sec) == sizeof (time_t) ? 1 : -1];
+
+/* Check that sigset_t is defined. */
+sigset_t t2;
+