diff --git a/paddle/fluid/operators/mkldnn_activation_op.h b/paddle/fluid/operators/mkldnn_activation_op.h
index 083d03ebe610521c5a4beb7b977a8179700bcf40..f26a165b5a59f01f864d62bbf798f4cbffa65371 100644
--- a/paddle/fluid/operators/mkldnn_activation_op.h
+++ b/paddle/fluid/operators/mkldnn_activation_op.h
@@ -60,7 +60,7 @@ class MKLDNNActivationGradKernel
   }
 };
 
-namespace {
+namespace {  // NOLINT
 framework::OpKernelType GetKernelType(
     const framework::ExecutionContext& ctx,
     const framework::OperatorWithKernel& oper) {