Windows doesn't support poll(2) or fcntl(2) so #ifdef it out in send_to_kdc.c.

lib/krb5/krb5_locl.h

@@ -47,7 +47,9 @@
 #include <stdlib.h>
 #include <limits.h>
 
+#ifdef HAVE_POLL_H
 #include <sys/poll.h>
+#endif
 
 #include <krb5-types.h>
 

lib/krb5/send_to_kdc.c

@@ -47,6 +47,7 @@ struct send_to_kdc {
 static int
 timed_connect(int s, struct addrinfo *addr, time_t tmout)
 {
+#ifdef HAVE_POLL
     socklen_t sl;
     int so_err;
     int flags;
@@ -88,6 +89,9 @@ timed_connect(int s, struct addrinfo *addr, time_t tmout)
 	return -1;
 
     return 0;
+#else
+    return connect(s, addr->ai_addr, addr->ai_addrlen);
+#endif
 }
 
 /*