diff --git a/src/cryptonote_basic/cryptonote_format_utils.cpp b/src/cryptonote_basic/cryptonote_format_utils.cpp
index 1c28ca4d8..3c760493f 100644
--- a/src/cryptonote_basic/cryptonote_format_utils.cpp
+++ b/src/cryptonote_basic/cryptonote_format_utils.cpp
@@ -994,7 +994,7 @@ namespace cryptonote
     block_hashes_cached = block_hashes_cached_count;
   }
   //---------------------------------------------------------------
-  crypto::secret_key encrypt_key(const crypto::secret_key &key, const std::string &passphrase)
+  crypto::secret_key encrypt_key(crypto::secret_key key, const std::string &passphrase)
   {
     crypto::hash hash;
     crypto::cn_slow_hash(passphrase.data(), passphrase.size(), hash);
@@ -1002,7 +1002,7 @@ namespace cryptonote
     return key;
   }
   //---------------------------------------------------------------
-  crypto::secret_key decrypt_key(const crypto::secret_key &key, const std::string &passphrase)
+  crypto::secret_key decrypt_key(crypto::secret_key key, const std::string &passphrase)
   {
     crypto::hash hash;
     crypto::cn_slow_hash(passphrase.data(), passphrase.size(), hash);
diff --git a/src/cryptonote_basic/cryptonote_format_utils.h b/src/cryptonote_basic/cryptonote_format_utils.h
index f88310c4c..aebeaa6f4 100644
--- a/src/cryptonote_basic/cryptonote_format_utils.h
+++ b/src/cryptonote_basic/cryptonote_format_utils.h
@@ -226,8 +226,8 @@ namespace cryptonote
   bool is_valid_decomposed_amount(uint64_t amount);
   void get_hash_stats(uint64_t &tx_hashes_calculated, uint64_t &tx_hashes_cached, uint64_t &block_hashes_calculated, uint64_t & block_hashes_cached);
 
-  crypto::secret_key encrypt_key(const crypto::secret_key &key, const std::string &passphrase);
-  crypto::secret_key decrypt_key(const crypto::secret_key &key, const std::string &passphrase);
+  crypto::secret_key encrypt_key(crypto::secret_key key, const std::string &passphrase);
+  crypto::secret_key decrypt_key(crypto::secret_key key, const std::string &passphrase);
 #define CHECKED_GET_SPECIFIC_VARIANT(variant_var, specific_type, variable_name, fail_return_val) \
   CHECK_AND_ASSERT_MES(variant_var.type() == typeid(specific_type), fail_return_val, "wrong variant type: " << variant_var.type().name() << ", expected " << typeid(specific_type).name()); \
   specific_type& variable_name = boost::get<specific_type>(variant_var);