Autosar Guidelines C++14  example code compile list(2)Rule A0-1-2 The value returned by a function 

Guidelines for the use of the C++14 language in critical and
safety-related systems Sample code compile list(1)
https://www.autosar.org/fileadmin/user_upload/standards/adaptive/17-03/AUTOSAR_RS_CPP14Guidelines.pdf

Autosar Guidelines C++14 example code compile list
https://qiita.com/kaizen_nagoya/items/8ccbf6675c3494d57a76

# 目的(purpose)
AutosarのC++ GuidelineをOS, 制御のプログラムで利用するにあたって、(1)hosted, freestandingの何を基本にすべきか。(2)C++2014,C++2017, C++202aの何を用いると良いか, (3)どの処理系を併用すると良いかを検討するため、-std=c++14, -std=c++17, -std=c++2aの3種類で、複数のコンパイラでコンパイルすることにより、誤(error)、警告(warning)、関数・変数連携(link)、出力(output)、にどのような影響があるかを確認する。
#成果(outcome)
複数の処理系の特徴が明確になるとともに、各標準段階, hosted, freestandingの特徴と課題を明確にする。


# A0-1-2.cpp
## 算譜(source code)

```c++:A0-1-2.cpp
//Guidelines for the use of the C++14 language in critical and safety-related systems
const char* msg= "Rule A0-1-2 (required, implementation, automated) The value returned by a function having a non-void return type that is not an overloaded operator shall be used.(2) A0-1-2.cpp";
//https://www.autosar.org/fileadmin/user_upload/standards/adaptive/17-03/AUTOSAR_RS_CPP14Guidelines.pdf
// There is no description about Autosar declear hosted or freestanding.
// If the Autosar intended both depending on the cases, autosar.h can choose one.
// Compile with -DHOSTED work as  hosted environment, -DFREESTANDING work as freestanding


///start AUTOSAR: From here to the "///end AUTOSAR" is from AUTOSAR without code having /// comment in line.
// $Id: A0-1-2.cpp 271687 2017-03-23 08:57:35Z piotr.tanski $
#include "autosar.h"/// add header file https://qiita.com/kaizen_nagoya/items/4bde8f21ab059b96cf2a
#include <algorithm>
#include <cstdint>
#include <vector>

using namespace std;/// add using

std::uint8_t fn1() noexcept
{
  return 0U;
}

void fn2() noexcept
{
  std::uint8_t x = fn1();    // Compliant
  fn1();                     // Non-compliant
  static_cast<void>(fn1());  // Compliant by exception
  cout <<"f2:fn1()="<< x<<endl; /// add output
}
void fn3()
{
  std::vector<std::int8_t> v{0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5};
  std::unique(v.begin(), v.end());                 // Non-compliant
  cout <<"fn3"<<v[10]<< endl;                    /// add output
  v.erase(std::unique(v.begin(), v.end()), v.end());  // Compliant
}
///end AUTOSAR
int main() {
  cout <<"fn1()="<<fn1()<<endl;
  fn2();
  fn3();

  cout<< msg << endl;
  ShutdownOS()  EXIT_SUCCESS;
/// Autosar OS 7.1.2.2 Undefined Behaviour in OSEK OS
/// OS425 If ShutdownOS is called and ShutdownHook() returns then the operating system shall disable all interrupts and enter an endless loop.
}
```
## 編纂・実行結果(compile and go)

```shell-session:cpa.sh
$ ../cpa.sh a0-1-2
$ clang++ a0-1-2.cpp -std=c++14 -Wall
fn1()=
f2:fn1()=
fn3
Rule A0-1-2 (required, implementation, automated) The value returned by a function having a non-void return type that is not an overloaded operator shall be used.(2) A0-1-2.cpp
rm: a0-1-2l13: No such file or directory
$ clang++ a0-1-2.cpp -std=c++17 -Wall
fn1()=
f2:fn1()=
fn3
Rule A0-1-2 (required, implementation, automated) The value returned by a function having a non-void return type that is not an overloaded operator shall be used.(2) A0-1-2.cpp
$ clang++ a0-1-2.cpp -std=c++2a -Wall
fn1()=
f2:fn1()=
fn3
Rule A0-1-2 (required, implementation, automated) The value returned by a function having a non-void return type that is not an overloaded operator shall be used.(2) A0-1-2.cpp

$ g++-8 a0-1-2.cpp -std=c++14  -Wall
fn1()=
f2:fn1()=
fn3
Rule A0-1-2 (required, implementation, automated) The value returned by a function having a non-void return type that is not an overloaded operator shall be used.(2) A0-1-2.cpp
$ g++-8 a0-1-2.cpp -std=c++17  -Wall
fn1()=
f2:fn1()=
fn3
Rule A0-1-2 (required, implementation, automated) The value returned by a function having a non-void return type that is not an overloaded operator shall be used.(2) A0-1-2.cpp
$ g++-8 a0-1-2.cpp -std=c++2a  -Wall
fn1()=
f2:fn1()=
fn3
Rule A0-1-2 (required, implementation, automated) The value returned by a function having a non-void return type that is not an overloaded operator shall be used.(2) A0-1-2.cpp
```

### Visual Studio 2017

```
>cl A0-1-2.cpp /EHsc
Microsoft(R) C/C++ Optimizing Compiler Version 19.15.26726 for x64
Copyright (C) Microsoft Corporation.  All rights reserved.

A0-1-2.cpp
Microsoft (R) Incremental Linker Version 14.15.26726.0
Copyright (C) Microsoft Corporation.  All rights reserved.

/out:A0-1-2.exe
A0-1-2.obj

C:\Users\Administrator\Documents>A0-1-2.exe
fn1()=
f2:fn1()=
fn3
Rule A0-1-2 (required, implementation, automated) The value returned by a function having a non-void return type that is not an overload
```
# 検討事項(agenda)
### 1. 自律(freestanding)環境. 接待(hosted)環境
C++N4606 1.4 Implementation compliance p.4
### 2.対応OSの水準、対応通信規約、応用機能による分類 freestanding用の関数、ライブラリ等
未着手
### 3.C++2014, C++2017, C++202aの比較項目 
本件なし
### 4.clang++, g++の比較検討項目 
本件なし
### 5. Visual Studio 2017 /Wall (警告)

visual studio 2017 autosar warning 一部
https://researchmap.jp/jox2zzdpw-1797580/#_1797580

visual studio 2017 autosar warning 全部
https://researchmap.jp/mud6rglqu-45645/?action=multidatabase_action_main_filedownload&download_flag=1&upload_id=177133&metadata_id=25961

# 参考文献(reference)
Autosar Guidelines C++14 example code compile list(1-169) 
https://qiita.com/kaizen_nagoya/items/8ccbf6675c3494d57a76

プログラミング言語教育のXYZ
https://qiita.com/kaizen_nagoya/items/1950c5810fb5c0b07be4
プログラミング言語教育のXYZ(youtube)
https://www.youtube.com/watch?v=He1_tg4px-w&t=486s

C++N4741 2018
Working Draft, Standard for Programming Language C++
http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/n4741.pdf
C++N4741, 2018 Standard Working Draft on ISO/IEC 14882 sample code compile list
https://qiita.com/kaizen_nagoya/items/3294c014044550896010

C++N4606 2016
Working Draft, Standard for Programming Language C++
http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/n4606.pdf
C++N4606, 2016符号断片編纂一覧(example code compile list)
 Working Draft 2016, ISO/IEC 14882(1)
https://qiita.com/kaizen_nagoya/items/df5d62c35bd6ed1c3d43/

CEDD(Compile Error Driven Design) 
初めての　CEDD(Compile Error Driven Design) ８回直してコンパイル。
https://qiita.com/kaizen_nagoya/items/9494236aa1753f3fd1e1

コンパイルエラーを記録するとよい理由7つ
https://qiita.com/kaizen_nagoya/items/85c0e92b206883140e89

C Puzzle Bookの有り難み5つ、C言語規格及びCコンパイラの特性を認識
https://qiita.com/kaizen_nagoya/items/d89a48c1536a02ecdec9

C言語（C++)に対する誤解、曲解、無理解、爽快。
https://qiita.com/kaizen_nagoya/items/3f3992c9722c1cee2e3a

Qiitaに投稿するCのStyle例(暫定)
https://qiita.com/kaizen_nagoya/items/946df1528a6a1ef2bc0d

C++N4606 Working Draft 2016, ISO/IEC 14882, C++ standardのコード断片をコンパイルするためにしていること
https://qiita.com/kaizen_nagoya/items/a8d7ee2f2e29e76c19c1

コンパイル用shell script C版(clangとgcc)とC++版(clang++とg++)
https://qiita.com/kaizen_nagoya/items/74220c0577a512c2d7da

[C][C++]の国際規格案の例題をコンパイルするときの課題７つ。
https://qiita.com/kaizen_nagoya/items/5f4b155030259497c4de

docker gnu(gcc/g++) and llvm(clang/clang++)
https://qiita.com/drafts/059874ea39c4de64c0f7

 Coding Rules(0) C Secure , MISRA and so on 
 https://qiita.com/kaizen_nagoya/items/400725644a8a0e90fbb0

Ethernet 記事一覧　Ethernet(0)
https://qiita.com/kaizen_nagoya/items/88d35e99f74aefc98794

Wireshark 一覧 wireshark(0)、Ethernet(48) 
https://qiita.com/kaizen_nagoya/items/fbed841f61875c4731d0

線網（Wi-Fi）空中線(antenna)(0) 記事一覧(118/300目標)
https://qiita.com/kaizen_nagoya/items/5e5464ac2b24bd4cd001

OSEK OS設計の基礎　OSEK(100)
https://qiita.com/kaizen_nagoya/items/7528a22a14242d2d58a3

Error一覧(C/C++, python, bash...) Error(0)
https://qiita.com/kaizen_nagoya/items/48b6cbc8d68eae2c42b8

なぜdockerで機械学習するか 書籍・ソース一覧作成中 (目標100)
https://qiita.com/kaizen_nagoya/items/ddd12477544bf5ba85e2

言語処理100本ノックをdockerで。python覚えるのに最適。:10+12
https://qiita.com/kaizen_nagoya/items/7e7eb7c543e0c18438c4

プログラムちょい替え（0）一覧:4件
https://qiita.com/kaizen_nagoya/items/296d87ef4bfd516bc394

TOPPERSまとめ　#名古屋のIoTは名古屋のOSで
https://qiita.com/kaizen_nagoya/items/9026c049cb0309b9d451

docker(0) 資料集
https://qiita.com/kaizen_nagoya/items/45699eefd62677f69c1d

Qiita-dockerお宝鑑定団
https://qiita.com/kaizen_nagoya/items/509e125263559b5aed5b

The C++ Standard Library: clang++とg++でコンパイルしてみた(まとめ):14件
https://qiita.com/kaizen_nagoya/items/9bdfaa392443d13e5759

C++17 - The Complete Guide clang++とg++でコンパイルしてみた(まとめ):4件
https://qiita.com/kaizen_nagoya/items/c000f307e642990781e1

C++N3242, 2011, ISO/IEC 14882, C++ standard(1) Example code compile list
https://qiita.com/kaizen_nagoya/items/685b5c1a2c17c1bf1318

C++N4606 Working Draft 2016, ISO/IEC 14882, C++ standard(1) Example code compile list
https://qiita.com/kaizen_nagoya/items/df5d62c35bd6ed1c3d43/

C++N4741, 2018 Standard Working Draft on ISO/IEC 14882 sample code compile list
https://qiita.com/kaizen_nagoya/items/3294c014044550896010

C++N4910:2022 Standard Working Draft on ISO/IEC 14882(0) sample code compile list
https://qiita.com/kaizen_nagoya/items/fc957ddddd402004bb91

Autosar Guidelines C++14 example code compile list(1-169)
https://qiita.com/kaizen_nagoya/items/8ccbf6675c3494d57a76

プログラマによる、プログラマのための、統計と確率のプログラミングとその後 統計と確率一覧（０）
https://qiita.com/kaizen_nagoya/items/6e9897eb641268766909

一覧の一覧( The directory of directories of mine.) Qiita(100)
https://qiita.com/kaizen_nagoya/items/7eb0e006543886138f39

＜この記事は個人の過去の経験に基づく個人の感想です。現在所属する組織、業務とは関係がありません。＞
This article is an individual impression based on the individual's experience. It has nothing to do with the organization or business to which I currently belong.
# 文書履歴(document history)
ver 0.10 初稿 20180606
ver 0.11 一覧追記 20180613
ver 0.12 参考文献欄追記 20180616
ver 0.20 Visual Studio 2017追記　20180915
### 最後までおよみいただきありがとうございました。
いいね　💚、フォローをお願いします。
####  Thank you very much for reading to the last sentence.
Please press the like icon 💚　and follow me for your happy life.