diff --git a/src/rpc.cpp b/src/rpc.cpp
index a67f7fc9471..33108948d3c 100644
--- a/src/rpc.cpp
+++ b/src/rpc.cpp
@@ -1301,7 +1301,7 @@ void ThreadCleanWalletPassphrase(void* parg)
             if (nWalletUnlockTime < nMyWakeTime)
                 nWalletUnlockTime = nMyWakeTime;
         }
-        free(parg);
+        delete (int*)parg;
         return;
     }