diff --git a/include/fc/crypto/elliptic.hpp b/include/fc/crypto/elliptic.hpp
index dd60da7..7d3046f 100644
--- a/include/fc/crypto/elliptic.hpp
+++ b/include/fc/crypto/elliptic.hpp
@@ -218,8 +218,8 @@ namespace fc {
 
      struct range_proof_info
      {
-         int          exp;
-         int          mantissa;
+         int64_t      exp;
+         int64_t      mantissa;
          uint64_t     min_value;
          uint64_t     max_value;
      };