fix mac compile

Author: JiayiFeng

paddle/fluid/framework/details/multi_devices_graph_builder.h

@@ -47,7 +47,7 @@ class MultiDevSSAGraphBuilder : public SSAGraphBuilder {
 #endif
 
   std::unique_ptr<SSAGraph> Build(const ProgramDesc &program) const override;
-  int GetVarDeviceID(const std::string &varname) const;
+  int GetVarDeviceID(const std::string &varname) const override;
 
  private:
   void CreateOpHandleIOs(SSAGraph *result, const OpDesc &op,

paddle/fluid/framework/parallel_executor.cc

@@ -121,7 +121,7 @@ ParallelExecutor::ParallelExecutor(
 #endif
   }
 
-  builder_ = std::move(builder_factory.Create());
+  builder_ = builder_factory.Create();
   member_->executor_.reset(new details::ThreadedSSAGraphExecutor(
       exec_strategy, member_->local_scopes_, places,
       builder_->Build(main_program)));