1 files changed, 2 insertions, 0 deletions
diff --git a/src/rpc/rpc_payment.h b/src/rpc/rpc_payment.h
index f6832fd34..20117985f 100644
--- a/src/rpc/rpc_payment.h
+++ b/src/rpc/rpc_payment.h
@@ -31,6 +31,7 @@
 #include <string>
 #include <unordered_set>
 #include <unordered_map>
+#include <boost/thread/mutex.hpp>
 #include <boost/serialization/version.hpp>
 #include "cryptonote_basic/blobdatatype.h"
 #include "cryptonote_basic/cryptonote_basic.h"
@@ -139,6 +140,7 @@ namespace cryptonote
     uint64_t m_nonces_stale;
     uint64_t m_nonces_bad;
     uint64_t m_nonces_dupe;
+    mutable boost::mutex mutex;
   };
 }