diff --git a/ncat/ncat_connect.c b/ncat/ncat_connect.c
index 7146f9c50..b3b0efd9c 100644
--- a/ncat/ncat_connect.c
+++ b/ncat/ncat_connect.c
@@ -140,6 +140,7 @@
 #include <unistd.h>
 #include <netdb.h>
 #endif
+#include <stddef.h>
 #include <stdlib.h>
 #include <string.h>
 #include <stdio.h>