diff --git a/repos/base/include/base/rpc_server.h b/repos/base/include/base/rpc_server.h
index 0061645c8b..6749849d22 100644
--- a/repos/base/include/base/rpc_server.h
+++ b/repos/base/include/base/rpc_server.h
@@ -99,7 +99,7 @@ class Genode::Rpc_dispatcher : public RPC_INTERFACE
 		}
 
 		template <typename ARG>
-		ARG _read_arg(Ipc_unmarshaller &msg, Rpc_arg_out)
+		ARG _read_arg(Ipc_unmarshaller &, Rpc_arg_out)
 		{
 			return ARG();
 		}