Include ws2tcpip.h in order to get in6_addr It's currently required in src/openssl_stream.c only.
diff --git a/src/common.h b/src/common.h
index a8f60fe..d798548 100644
--- a/src/common.h
+++ b/src/common.h
@@ -33,6 +33,7 @@
# include <direct.h>
# include <winsock2.h>
# include <windows.h>
+# include <ws2tcpip.h>
# include "win32/msvc-compat.h"
# include "win32/mingw-compat.h"
# include "win32/error.h"