Remove call_once.h (#9764)

* Remove call_once.h

* "fix ci"

paddle/fluid/platform/call_once.h

@@ -1,57 +0,0 @@
-/* Copyright (c) 2016 PaddlePaddle Authors. All Rights Reserved.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License. */
-
-#pragma once
-
-#include <mutex>
-
-namespace paddle {
-namespace platform {
-
-/*
- The current implementation of std::call_once has a bug described in
- https://stackoverflow.com/questions/41717579/stdcall-once-hangs-on-second-call-after-callable-threw-on-first-call.
- This is likely caused by a deeper bug of pthread_once, which is discussed in
- https://patchwork.ozlabs.org/patch/482350/
-
- This wrap is a hack to avoid this bug.
-*/
-template <typename Callable, typename... Args>
-inline void call_once(std::once_flag& flag, Callable&& f, Args&&... args) {
-  bool good = true;
-  std::exception ex;
-  try {
-    std::call_once(flag,
-                   [&](Args&&... args) {
-                     try {
-                       f(args...);
-                     } catch (const std::exception& e) {
-                       ex = e;
-                       good = false;
-                     } catch (...) {
-                       ex = std::runtime_error("excption caught in call_once");
-                       good = false;
-                     }
-                   },
-                   args...);
-  } catch (std::system_error& x) {
-    throw std::runtime_error("call once failed");
-  }
-  if (!good) {
-    throw std::exception(ex);
-  }
-}
-
-}  // namespace platform
-}  // namespace paddle

paddle/fluid/platform/dynload/nccl.h

@@ -18,7 +18,6 @@ limitations under the License. */
 
 #include <mutex>  // NOLINT
 
-#include "paddle/fluid/platform/call_once.h"
 #include "paddle/fluid/platform/dynload/dynamic_loader.h"
 
 namespace paddle {