diff --git a/lib/ftp.c b/lib/ftp.c
index 0ac5d4d2b..1acf2dd7e 100644
--- a/lib/ftp.c
+++ b/lib/ftp.c
@@ -84,6 +84,10 @@
 #include "ssluse.h"
 #include "connect.h"
 
+#if defined(HAVE_INET_NTOA_R) && !defined(HAVE_INET_NTOA_R_DECL)
+#include "inet_ntoa_r.h"
+#endif
+
 #define _MPRINTF_REPLACE /* use our functions only */
 #include <curl/mprintf.h>