1 files changed, 1 insertions, 0 deletions

diff --git a/lib/basic_op.cc b/lib/basic_op.cc
index c247493..fa659ac 100644
--- a/lib/basic_op.cc
+++ b/lib/basic_op.cc
@@ -1,20 +1,21 @@
 #include <time.h>
 #include <cassert>
 #include <openssl/sha.h>
 #include <openssl/hmac.h>
 #include <opkele/data.h>
 #include <opkele/basic_op.h>
 #include <opkele/exception.h>
 #include <opkele/util.h>
+#include <opkele/util-internal.h>
 #include <opkele/uris.h>
 
 namespace opkele {
 
     void basic_OP::reset_vars() {
         assoc.reset();
         return_to.clear(); realm.clear();
         claimed_id.clear(); identity.clear();
         invalidate_handle.clear();
     }
 
     bool basic_OP::has_return_to() const {