Guidelines for the use of the C++14 language in critical and
safety-related systems Sample code compile list(113)
https://www.autosar.org/fileadmin/user_upload/standards/adaptive/17-03/AUTOSAR_RS_CPP14Guidelines.pdf
Autosar Guidelines C++14, example code compile list will be listed.
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、以下を検討する。
(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。
-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。
各標準段階の違いを明確にする。
hostedまたはfreestandingの特徴と課題を明確にする。
A13-6-1.cpp
算譜(source code)
A13-6-1.cpp
//Guidelines for the use of the C++14 language in critical and safety-related systems
const char* msg="Rule A13-6-1 (required, implementation, automated)Digit sequences separators ’ shall only be used as follows: (1) for decimal,every 3 digits, (2) for hexadecimal, every 2 digits, (3) for binary, every 4 digits.(113)A13-6-1.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" are from the AUTOSAR code without some code having /// comment in line.
// $Id: A13-6-1.cpp 271687 2017-03-23 08:57:35Z piotr.tanski $
#include <cstdint>
void fn() noexcept
{
std::uint32_t decimal1 = 3'000'000; // Compliant
std::uint32_t decimal2 = 4'500; // Compliant
std::uint32_t decimal3 = 54'00'30; // Non-compliant
float decimal4 = 3.141'592'653; // Compliant
float decimal5 = 3.1'4159'265'3; // Non-compliant
std::uint32_t hex1 = 0xFF'FF'FF'FF; // Compliant
std::uint32_t hex2 = 0xFAB'1'FFFFF; // Non-compliant
std::uint8_t binary1 = 0b1001'0011; // Compliant
std::uint8_t binary2 = 0b10'00'10'01; // Non-compliant
cout <<"decimal1="<<decimal1<<" decimal2="<<decimal2<<" decimal3="<<decimal3<<" decimal4="<<decimal4;/// @
cout <<" decimal5="<<decimal5<<" hex1="<<hex1<<" hex2="<<hex2<<" binary1="<<binary1<<" binary2="<<binary2<<endl;/// @ 2lines for output
}
/// @ end AUTOSAR
int start() { /// @{} for start
fn();
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 a13-6-1
$ clang++ a13-6-1.cpp -I./ -std=c++14 -Wall
a13-6-1.cpp:23:23: warning: implicit conversion from 'long' to 'std::uint32_t' (aka 'unsigned int') changes value from
67295510527 to 2871001087 [-Wconstant-conversion]
std::uint32_t hex2 = 0xFAB'1'FFFFF; // Non-compliant
~~~~ ^~~~~~~~~~~~~
1 warning generated.
decimal1=3000000 decimal2=4500 decimal3=540030 decimal4=3.14159 decimal5=3.14159 hex1=4294967295 hex2=2871001087 binary1=? binary2=?
Rule A13-6-1 (required, implementation, automated)Digit sequences separators ’ shall only be used as follows: (1) for decimal,every 3 digits, (2) for hexadecimal, every 2 digits, (3) for binary, every 4 digits.(113)A13-6-1.cpp
$ clang++ a13-6-1.cpp -I./ -std=c++17 -Wall
a13-6-1.cpp:23:23: warning: implicit conversion from 'long' to 'std::uint32_t' (aka 'unsigned int') changes value from
67295510527 to 2871001087 [-Wconstant-conversion]
std::uint32_t hex2 = 0xFAB'1'FFFFF; // Non-compliant
~~~~ ^~~~~~~~~~~~~
1 warning generated.
decimal1=3000000 decimal2=4500 decimal3=540030 decimal4=3.14159 decimal5=3.14159 hex1=4294967295 hex2=2871001087 binary1=? binary2=?
Rule A13-6-1 (required, implementation, automated)Digit sequences separators ’ shall only be used as follows: (1) for decimal,every 3 digits, (2) for hexadecimal, every 2 digits, (3) for binary, every 4 digits.(113)A13-6-1.cpp
$ clang++ a13-6-1.cpp -I./ -std=c++2a -Wall
a13-6-1.cpp:23:23: warning: implicit conversion from 'long' to 'std::uint32_t' (aka 'unsigned int') changes value from
67295510527 to 2871001087 [-Wconstant-conversion]
std::uint32_t hex2 = 0xFAB'1'FFFFF; // Non-compliant
~~~~ ^~~~~~~~~~~~~
1 warning generated.
decimal1=3000000 decimal2=4500 decimal3=540030 decimal4=3.14159 decimal5=3.14159 hex1=4294967295 hex2=2871001087 binary1=? binary2=?
Rule A13-6-1 (required, implementation, automated)Digit sequences separators ’ shall only be used as follows: (1) for decimal,every 3 digits, (2) for hexadecimal, every 2 digits, (3) for binary, every 4 digits.(113)A13-6-1.cpp
$ g++-8 a13-6-1.cpp -I./ -std=c++14 -Wall
a13-6-1.cpp: In function 'void fn()':
a13-6-1.cpp:23:23: warning: unsigned conversion from 'long int' to 'uint32_t' {aka 'unsigned int'} changes value from '67295510527' to '2871001087' [-Woverflow]
std::uint32_t hex2 = 0xFAB'1'FFFFF; // Non-compliant
^~~~~~~~~~~~~
decimal1=3000000 decimal2=4500 decimal3=540030 decimal4=3.14159 decimal5=3.14159 hex1=4294967295 hex2=2871001087 binary1=? binary2=?
Rule A13-6-1 (required, implementation, automated)Digit sequences separators ’ shall only be used as follows: (1) for decimal,every 3 digits, (2) for hexadecimal, every 2 digits, (3) for binary, every 4 digits.(113)A13-6-1.cpp
$ g++-8 a13-6-1.cpp -I./ -std=c++17 -Wall
a13-6-1.cpp: In function 'void fn()':
a13-6-1.cpp:23:23: warning: unsigned conversion from 'long int' to 'uint32_t' {aka 'unsigned int'} changes value from '67295510527' to '2871001087' [-Woverflow]
std::uint32_t hex2 = 0xFAB'1'FFFFF; // Non-compliant
^~~~~~~~~~~~~
decimal1=3000000 decimal2=4500 decimal3=540030 decimal4=3.14159 decimal5=3.14159 hex1=4294967295 hex2=2871001087 binary1=? binary2=?
Rule A13-6-1 (required, implementation, automated)Digit sequences separators ’ shall only be used as follows: (1) for decimal,every 3 digits, (2) for hexadecimal, every 2 digits, (3) for binary, every 4 digits.(113)A13-6-1.cpp
$ g++-8 a13-6-1.cpp -I./ -std=c++2a -Wall
a13-6-1.cpp: In function 'void fn()':
a13-6-1.cpp:23:23: warning: unsigned conversion from 'long int' to 'uint32_t' {aka 'unsigned int'} changes value from '67295510527' to '2871001087' [-Woverflow]
std::uint32_t hex2 = 0xFAB'1'FFFFF; // Non-compliant
^~~~~~~~~~~~~
decimal1=3000000 decimal2=4500 decimal3=540030 decimal4=3.14159 decimal5=3.14159 hex1=4294967295 hex2=2871001087 binary1=? binary2=?
Rule A13-6-1 (required, implementation, automated)Digit sequences separators ’ shall only be used as follows: (1) for decimal,every 3 digits, (2) for hexadecimal, every 2 digits, (3) for binary, every 4 digits.(113)A13-6-1.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 20180612