Autosar Guidelines C++14, example code compile list(74)Rule A8-5-1 In an initialization list, the order of initialization

Guidelines for the use of the C++14 language in critical and
safety-related systems Sample code compile list(74)
https://www.autosar.org/fileadmin/user_upload/standards/adaptive/17-03/AUTOSAR_RS_CPP14Guidelines.pdf
Autosar Guidelines C++14, example code compile list(

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のどちらを基本にすべきか。(2)C++2014,C++2017, C++202aのどれを用いると良いか, (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。

A8-5-1.cpp

算譜(source code)

A8-5-1.cpp

//Guidelines for the use of the C++14 language in critical and safety-related systems
const char* msg="Rule A8-5-1 (required, implementation, automated)In an initialization list, the order of initialization shall be following: (1) virtual base classes in depth and left to right order of the inheritance graph, (2) direct base classes in left to right order of inheritance list, (3) non-static data members in the order they were declared in the class definition.(74)A8-5-1.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.

#include "autosar.h"/// @line add header file https://qiita.com/kaizen_nagoya/items/4bde8f21ab059b96cf2a

using namespace std;/// @line add using

///start AUTOSAR: From here to the "///end AUTOSAR" is from AUTOSAR without code having /// comment in line.
// $Id: A8-5-1.cpp 271696 2017-03-23 09:23:09Z piotr.tanski $
#include <cstdint>
#include <string>
class A
{
};
class B
{
};
class C : public virtual B, public A
{
public:
  C() : B(), A(), s() {} // Compliant

// C() : A(), B() { } // Non-compliant - incorrect order of initialization

private:
  std::string s;
};
class D
{
};
class E
{
};
class F : public virtual A, public B, public virtual D, public E
{
public:
  F() : A(), D(), B(), E(), number1(0), number2(0U) {} // Compliant
  F(F const& oth)
    : B(), E(), A(), D(), number1(oth.number1), number2(oth.number2)
  {
  } // Non-compliant - incorrect
// order of initialization

private:
  std::int32_t number1;
  std::uint8_t number2;
};
///end AUTOSAR
int start() { /// @{} for start
  cout<< msg << endl;
  ShutdownOS()  EXIT_SUCCESS;
/// Autosar OS 3.1.1, 2009: 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)

cpa.sh

$ ../cpa.sh a8-5-1
$ clang++ a8-5-1.cpp -I./ -std=c++14 -Wall
a8-5-1.cpp:43:9: warning: base class 'E' will be initialized after base 'A' [-Wreorder]
 : B(), E(), A(), D(), number1(oth.number1), number2(oth.number2)
        ^
1 warning generated.
Rule A8-5-1 (required, implementation, automated)In an initialization list, the order of initialization shall be following: (1) virtual base classes in depth and left to right order of the inheritance graph, (2) direct base classes in left to right order of inheritance list, (3) non-static data members in the order they were declared in the class definition.(74)A8-5-1.cpp
$ clang++ a8-5-1.cpp  -I./ -std=c++17 -Wall
a8-5-1.cpp:43:9: warning: base class 'E' will be initialized after base 'A' [-Wreorder]
 : B(), E(), A(), D(), number1(oth.number1), number2(oth.number2)
        ^
1 warning generated.
Rule A8-5-1 (required, implementation, automated)In an initialization list, the order of initialization shall be following: (1) virtual base classes in depth and left to right order of the inheritance graph, (2) direct base classes in left to right order of inheritance list, (3) non-static data members in the order they were declared in the class definition.(74)A8-5-1.cpp
$ clang++ a8-5-1.cpp  -I./ -std=c++2a -Wall
a8-5-1.cpp:43:9: warning: base class 'E' will be initialized after base 'A' [-Wreorder]
 : B(), E(), A(), D(), number1(oth.number1), number2(oth.number2)
        ^
1 warning generated.
Rule A8-5-1 (required, implementation, automated)In an initialization list, the order of initialization shall be following: (1) virtual base classes in depth and left to right order of the inheritance graph, (2) direct base classes in left to right order of inheritance list, (3) non-static data members in the order they were declared in the class definition.(74)A8-5-1.cpp

$ g++-8 a8-5-1.cpp  -I./ -std=c++14  -Wall
a8-5-1.cpp: In copy constructor 'F::F(const F&)':
a8-5-1.cpp:43:65: warning: base 'E' will be initialized after [-Wreorder]
  : B(), E(), A(), D(), number1(oth.number1), number2(oth.number2)
                                                                 ^
a8-5-1.cpp:43:65: warning:   base 'A' [-Wreorder]
a8-5-1.cpp:42:2: warning:   when initialized here [-Wreorder]
  F(F const& oth)
  ^
Rule A8-5-1 (required, implementation, automated)In an initialization list, the order of initialization shall be following: (1) virtual base classes in depth and left to right order of the inheritance graph, (2) direct base classes in left to right order of inheritance list, (3) non-static data members in the order they were declared in the class definition.(74)A8-5-1.cpp
$ g++-8 a8-5-1.cpp  -I./ -std=c++17  -Wall
a8-5-1.cpp: In copy constructor 'F::F(const F&)':
a8-5-1.cpp:43:65: warning: base 'E' will be initialized after [-Wreorder]
  : B(), E(), A(), D(), number1(oth.number1), number2(oth.number2)
                                                                 ^
a8-5-1.cpp:43:65: warning:   base 'A' [-Wreorder]
a8-5-1.cpp:42:2: warning:   when initialized here [-Wreorder]
  F(F const& oth)
  ^
Rule A8-5-1 (required, implementation, automated)In an initialization list, the order of initialization shall be following: (1) virtual base classes in depth and left to right order of the inheritance graph, (2) direct base classes in left to right order of inheritance list, (3) non-static data members in the order they were declared in the class definition.(74)A8-5-1.cpp
$ g++-8 a8-5-1.cpp  -I./ -std=c++2a  -Wall
a8-5-1.cpp: In copy constructor 'F::F(const F&)':
a8-5-1.cpp:43:65: warning: base 'E' will be initialized after [-Wreorder]
  : B(), E(), A(), D(), number1(oth.number1), number2(oth.number2)
                                                                 ^
a8-5-1.cpp:43:65: warning:   base 'A' [-Wreorder]
a8-5-1.cpp:42:2: warning:   when initialized here [-Wreorder]
  F(F const& oth)
  ^
Rule A8-5-1 (required, implementation, automated)In an initialization list, the order of initialization shall be following: (1) virtual base classes in depth and left to right order of the inheritance graph, (2) direct base classes in left to right order of inheritance list, (3) non-static data members in the order they were declared in the class definition.(74)A8-5-1.cpp

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

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

clang++警告なし, g++警告あり

5 役立つまたは意味のある出力

参考文献(reference)

C++N4741 2018

Working Draft, Standard for Programming Language C++
http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/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/

文書履歴

ver 0.10 初稿 20180611