Missing #include on Win32

diff --git a/configure.ac b/configure.ac
index 931414e809adb40ba17a61a2fa02aa91bba2b937..26b0c09b147ffc82efd5f44a297bf2abeeeaae21 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -533,6 +533,7 @@ ac_cv_type_socklen_t,
 [#include <sys/types.h>
 #ifdef WIN32
 # include <winsock2.h>
+# include <ws2tcpip.h>
 #else
 # include <sys/socket.h>
 #endif]], [[socklen_t len; len = 0;]])],