Guidelines for the use of the C++14 language in critical and
safety-related systems Sample code compile list(55)
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。
#A6-6-1.cpp
##算譜(source code)
//Guidelines for the use of the C++14 language in critical and safety-related systems
const char* msg="Rule A6-6-1 (required, implementation, automated)The goto statement shall not be used.(55)A6-6-1.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: A6-6-1.cpp 271715 2017-03-23 10:13:51Z piotr.tanski $
#include <cstdint>
namespace
{
constexpr std::int32_t loopLimit = 100;
}
void f1(std::int32_t n) noexcept
{
if (n < 0)
{
//goto exit; // Non-compliant - jumping to exit from here crosses ptr
// pointer initialization, compilation
// error
}
std::int32_t* ptr = new std::int32_t(n);
// ...
exit:
delete ptr;
}
void f2() noexcept
{
// ...
goto error; // Non-compliant
// ...
error:; // Error handling and cleanup
}
void f3() noexcept
{
for (std::int32_t i = 0; i < loopLimit; ++i)
{
for (std::int32_t j = 0; j < loopLimit; ++j)
{
for (std::int32_t k = 0; k < loopLimit; ++k)
{
if ((i == j) && (j == k))
{
// ...
cout <<"i="<<i<<" j="<<j<<" k="<<k<<endl;/// @ line for output
goto loop_break; // Non-compliant
}
}
}
}
loop_break:; // ...
}
///end AUTOSAR
int start() { /// @{} for start
int32_t i=2048;
f1(i);
f2();
f3();
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 a6-6-1
$ clang++ a6-6-1.cpp -I./ -std=c++14 -Wall
a6-6-1.cpp:30:2: warning: unused label 'exit' [-Wunused-label]
exit:
^~~~~
1 warning generated.
i=0 j=0 k=0
Rule A6-6-1 (required, implementation, automated)The goto statement shall not be used.(55)A6-6-1.cpp
$ clang++ a6-6-1.cpp -I./ -std=c++17 -Wall
a6-6-1.cpp:30:2: warning: unused label 'exit' [-Wunused-label]
exit:
^~~~~
1 warning generated.
i=0 j=0 k=0
Rule A6-6-1 (required, implementation, automated)The goto statement shall not be used.(55)A6-6-1.cpp
$ clang++ a6-6-1.cpp -I./ -std=c++2a -Wall
a6-6-1.cpp:30:2: warning: unused label 'exit' [-Wunused-label]
exit:
^~~~~
1 warning generated.
i=0 j=0 k=0
Rule A6-6-1 (required, implementation, automated)The goto statement shall not be used.(55)A6-6-1.cpp
$ g++-8 a6-6-1.cpp -I./ -std=c++14 -Wall
a6-6-1.cpp: In function 'void f1(int32_t)':
a6-6-1.cpp:30:2: warning: label 'exit' defined but not used [-Wunused-label]
exit:
^~~~
i=0 j=0 k=0
Rule A6-6-1 (required, implementation, automated)The goto statement shall not be used.(55)A6-6-1.cpp
$ g++-8 a6-6-1.cpp -I./ -std=c++17 -Wall
a6-6-1.cpp: In function 'void f1(int32_t)':
a6-6-1.cpp:30:2: warning: label 'exit' defined but not used [-Wunused-label]
exit:
^~~~
i=0 j=0 k=0
Rule A6-6-1 (required, implementation, automated)The goto statement shall not be used.(55)A6-6-1.cpp
$ g++-8 a6-6-1.cpp -I./ -std=c++2a -Wall
a6-6-1.cpp: In function 'void f1(int32_t)':
a6-6-1.cpp:30:2: warning: label 'exit' defined but not used [-Wunused-label]
exit:
^~~~
i=0 j=0 k=0
Rule A6-6-1 (required, implementation, automated)The goto statement shall not be used.(55)A6-6-1.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
本件なし
###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 20180610