diff --git a/src/session_client.c b/src/session_client.c
index 8b851dd..abb6f37 100644
--- a/src/session_client.c
+++ b/src/session_client.c
@@ -1548,7 +1548,7 @@
  * @return Connected socket or -1 on error.
  */
 static int
-sock_connect(int timeout_ms, int *sock_pending, struct addrinfo *res, struct nc_keepalives *ka)
+sock_connect(int timeout_ms, int *sock_pending, struct addrinfo *res, const struct nc_keepalives *ka)
 {
     int flags, ret, error;
     int sock = -1;