fix dist train error (#11281)

* fix dist train error

* update by comment

paddle/fluid/framework/details/multi_devices_graph_builder.cc

@@ -464,9 +464,8 @@ void MultiDevSSAGraphBuilder::CreateDistTrainOp(SSAGraph *result,
 
 void MultiDevSSAGraphBuilder::CreateRPCOp(SSAGraph *result,
                                           const OpDesc &op) const {
-  auto &p = places_[0];
-  auto *s = local_scopes_[0];
-  result->ops_.emplace_back(new RPCOpHandle(op, s, p, op.Type()));
+  result->ops_.emplace_back(
+      new RPCOpHandle(op, local_scopes_[0], op.Type(), places_[0]));
 
   if (op.Type() == "send_barrier") {
     ConnectOp(result, result->ops_.back().get(), "send_vars");

paddle/fluid/framework/details/rpc_op_handle.cc

@@ -19,12 +19,12 @@ namespace framework {
 namespace details {
 
 RPCOpHandle::RPCOpHandle(const framework::OpDesc &op_desc,
-                         const Scope *local_scope, const platform::Place &place,
-                         const std::string &name)
+                         const Scope *local_scope, const std::string &name,
+                         const platform::Place &place)
     : op_(framework::OpRegistry::CreateOp(op_desc)),
       local_scope_(local_scope),
-      place_(place),
-      name_(name) {}
+      name_(name),
+      place_(place) {}
 
 void RPCOpHandle::RunImpl() {
   // TODO(wuyi): need further analysis whether wait VarDummyHandle.

paddle/fluid/framework/details/rpc_op_handle.h

@@ -29,7 +29,7 @@ namespace details {
 
 struct RPCOpHandle : public OpHandleBase {
   RPCOpHandle(const framework::OpDesc& op_desc, const Scope* local_scope,
-              const platform::Place& place, const std::string& name);
+              const std::string& name, const platform::Place& place);
 
   std::string Name() const override;
 
@@ -43,8 +43,8 @@ struct RPCOpHandle : public OpHandleBase {
  private:
   std::unique_ptr<OperatorBase> op_;
   const Scope* local_scope_;
-  const platform::Place& place_;
   const std::string name_;
+  platform::Place place_;
 };
 
 }  // namespace details