diff --git a/src/wallet/wallet_errors.h b/src/wallet/wallet_errors.h
index a0b9834e..79b5d06a 100644
--- a/src/wallet/wallet_errors.h
+++ b/src/wallet/wallet_errors.h
@@ -68,7 +68,7 @@ namespace tools
         return ss.str();
       }
 
-      virtual char const* what() const
+      virtual const char* what() const
       {
         m_what = to_string();
         return m_what.c_str();