C++N4606(245) 20.5.2.4 Tuple creation functions[tuple.creation]p552


#はじめに(Introduction)
C++N4606 Working Draft, Standard for Programming Language C++
http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/#mailing2016-11
http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/n4606.pdf

C++N4606は、ISO/IEC JTC1 SC22 WG21の作業原案(Working Draft)です。
公式のISO/IEC 14882原本ではありません。
ISO/IEC JTC1 SC22 WG21では、可能な限り作業文書を公開し、幅広い意見を求めています。
一連の記事はコード断片をコンパイルできる形にする方法を検討してコンパイル、リンク、実行して、規格案の原文と処理系(g++, Clang++)との違いを確認し、技術内容を検討し、ISO/IEC JTC1 SC22 WG21にフィードバックするために用います。
また、CERT C++, MISRA C++等のコーディング標準のコード断片をコンパイルする際の参考にさせていただこうと考えています。CERT C++, MISRA C++が標準化の動きとの時間的なずれがあれば確認できれば幸いです。また、boostライブラリとの関連、Linux OS, TOPPERSカーネル、g++(GCC), clang++(LLVM）との関係も調査中です。
何か、抜け漏れ、耳より情報がありましたらおしらせくださると幸いです。

##作業方針(sequence)
１）コンパイルエラーを収集する。
２）コンパイルエラーをなくす方法を検討する。
コンパイルエラーになる例を示すだけが目的のコードは、コンパイルエラーをなくすのではなく、コンパイルエラーの種類を収集するだけにする。
文法を示すのが目的のコード場合に、コンパイルエラーをなくすのに手間がかかる場合は、順次作業します。
３）リンクエラーをなくす方法を検討する。
文法を示すのが目的のコード場合に、リンクエラーをなくすのに手間がかかる場合は、順次作業します。
４）意味のある出力を作る。
コンパイル、リンクが通っても、意味のある出力を示そうとすると、コンパイル・リンクエラーが出て収拾できそうにない場合がある。順次作業します。

１）だけのものから４）まで進んだものと色々ある状態です。一歩でも前に進むご助言をお待ちしています。「検討事項」の欄に現状を記録するようにしています。

## C++N4606符号断片編纂一覧(example code compile list)
C++N4606 Working Draft 2016, ISO/IEC 14882, C++ standard(1) Example code compile list
https://qiita.com/kaizen_nagoya/items/df5d62c35bd6ed1c3d43/


## 編纂器(Compiler)
###clang++ --version
clang version 6.0.0 (tags/RELEASE_600/final)
Target: x86_64-apple-darwin17.4.0

###g++-7 --version
g++-7 (Homebrew GCC 7.3.0_1) 7.3.0
Copyright (C) 2017 Free Software Foundation, Inc.

#(245) 20.5.2.4 Tuple creation functions[tuple.creation]p552
##算譜(source code)

```c++:p552.cpp
// C++N4606 Committee Draft, Standard for Programming Language C++
// http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/n4606.pdf
#define msg "C++N4606(245) 20.5.2.4 Tuple creation functions[tuple.creation]p552.cpp"
// Edited by Dr. Ogawa Kiyoshi. Compile procedure and results record.

#include <iostream>
#include <cstdlib>
#include <cassert> // for constexpr
#include <tuple> // for allocate_arg_t
#include <string>
#include <utility>

#define EXPLICIT explicit

void f() {
  int i;
  float j;
  make_tuple(1, std::ref(i), std::cref(j));/// add std:: to ref and cref
  //creates a tuple of type
  std::tuple<int, int&, const float&>;/// add std:: to tuple
}

int main() {
  f();
  int i;
  std::string s;
  tie(i, std::ignore, s) = std::make_tuple(42, 3.14, "C++");/// add std:: to ignore and make_tupple
  // i == 42, s == "C++"
  std::cout << "i=" << i << " s="<< s << std::endl;
  std::cout<< msg << std::endl;
  return EXIT_SUCCESS;
}
```
##編纂・実行結果(compile and go)

```shell_session:cppall.sh
$ ./cppall.sh p552
$ clang++ p552.cpp -std=c++03 -Wall
p552.cpp:17:3: error: use of undeclared identifier 'make_tuple'
  make_tuple(1, std::ref(i), std::cref(j));/// add std:: to ref and cref
  ^
p552.cpp:19:8: error: no member named 'tuple' in namespace 'std'
  std::tuple<int, int&, const float&>;/// add std:: to tuple
  ~~~~~^
p552.cpp:19:17: error: expected '(' for function-style cast or type construction
  std::tuple<int, int&, const float&>;/// add std:: to tuple
             ~~~^
p552.cpp:25:15: error: no member named 'ignore' in namespace 'std'
  tie(i, std::ignore, s) = std::make_tuple(42, 3.14, "C++");/// add std:: to ignore and make_tupple
         ~~~~~^
p552.cpp:25:33: error: no member named 'make_tuple' in namespace 'std'
  tie(i, std::ignore, s) = std::make_tuple(42, 3.14, "C++");/// add std:: to ignore and make_tupple
                           ~~~~~^
5 errors generated.
$ clang++ p552.cpp -std=c++11 -Wall
p552.cpp:19:3: warning: declaration does not declare anything [-Wmissing-declarations]
  std::tuple<int, int&, const float&>;/// add std:: to tuple
  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1 warning generated.
i=42 s=C++
C++N4606(245) 20.5.2.4 Tuple creation functions[tuple.creation]p552.cpp
$ clang++ p552.cpp -std=c++17 -Wall
p552.cpp:19:3: warning: declaration does not declare anything [-Wmissing-declarations]
  std::tuple<int, int&, const float&>;/// add std:: to tuple
  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1 warning generated.
i=42 s=C++
C++N4606(245) 20.5.2.4 Tuple creation functions[tuple.creation]p552.cpp

$ g++-7 p552.cpp -std=c++03  -Wall
In file included from /usr/local/Cellar/gcc/7.3.0_1/include/c++/7.3.0/tuple:35:0,
                 from p552.cpp:9:
/usr/local/Cellar/gcc/7.3.0_1/include/c++/7.3.0/bits/c++0x_warning.h:32:2: error: #error This file requires compiler and library support for the ISO C++ 2011 standard. This support must be enabled with the -std=c++11 or -std=gnu++11 compiler options.
 #error This file requires compiler and library support \
  ^~~~~
p552.cpp: In function 'void f()':
p552.cpp:17:22: error: 'ref' is not a member of 'std'
   make_tuple(1, std::ref(i), std::cref(j));/// add std:: to ref and cref
                      ^~~
p552.cpp:17:35: error: 'cref' is not a member of 'std'
   make_tuple(1, std::ref(i), std::cref(j));/// add std:: to ref and cref
                                   ^~~~
p552.cpp:17:3: error: 'make_tuple' was not declared in this scope
   make_tuple(1, std::ref(i), std::cref(j));/// add std:: to ref and cref
   ^~~~~~~~~~
p552.cpp:19:8: error: 'tuple' is not a member of 'std'
   std::tuple<int, int&, const float&>;/// add std:: to tuple
        ^~~~~
p552.cpp:19:14: error: expected primary-expression before 'int'
   std::tuple<int, int&, const float&>;/// add std:: to tuple
              ^~~
p552.cpp: In function 'int main()':
p552.cpp:25:15: error: 'ignore' is not a member of 'std'
   tie(i, std::ignore, s) = std::make_tuple(42, 3.14, "C++");/// add std:: to ignore and make_tupple
               ^~~~~~
p552.cpp:25:3: error: 'tie' was not declared in this scope
   tie(i, std::ignore, s) = std::make_tuple(42, 3.14, "C++");/// add std:: to ignore and make_tupple
   ^~~
p552.cpp:25:3: note: suggested alternative: 'time'
   tie(i, std::ignore, s) = std::make_tuple(42, 3.14, "C++");/// add std:: to ignore and make_tupple
   ^~~
   time
p552.cpp:25:33: error: 'make_tuple' is not a member of 'std'
   tie(i, std::ignore, s) = std::make_tuple(42, 3.14, "C++");/// add std:: to ignore and make_tupple
                                 ^~~~~~~~~~
p552.cpp:25:33: note: suggested alternative: 'make_pair'
   tie(i, std::ignore, s) = std::make_tuple(42, 3.14, "C++");/// add std:: to ignore and make_tupple
                                 ^~~~~~~~~~
                                 make_pair

$ g++-7 p552.cpp -std=c++11  -Wall
p552.cpp: In function 'void f()':
p552.cpp:17:22: error: 'ref' is not a member of 'std'
   make_tuple(1, std::ref(i), std::cref(j));/// add std:: to ref and cref
                      ^~~
p552.cpp:17:35: error: 'cref' is not a member of 'std'
   make_tuple(1, std::ref(i), std::cref(j));/// add std:: to ref and cref
                                   ^~~~
p552.cpp:17:35: note: suggested alternative: 'prev'
   make_tuple(1, std::ref(i), std::cref(j));/// add std:: to ref and cref
                                   ^~~~
                                   prev
p552.cpp:17:3: error: 'make_tuple' was not declared in this scope
   make_tuple(1, std::ref(i), std::cref(j));/// add std:: to ref and cref
   ^~~~~~~~~~
p552.cpp:17:3: note: suggested alternative:
In file included from p552.cpp:9:0:
/usr/local/Cellar/gcc/7.3.0_1/include/c++/7.3.0/tuple:1448:5: note:   'std::make_tuple'
     make_tuple(_Elements&&... __args)
     ^~~~~~~~~~
p552.cpp:19:8: error: declaration does not declare anything [-fpermissive]
   std::tuple<int, int&, const float&>;/// add std:: to tuple
        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

$ g++-7 p552.cpp -std=c++17  -Wall
p552.cpp: In function 'void f()':
p552.cpp:17:22: error: 'ref' is not a member of 'std'
   make_tuple(1, std::ref(i), std::cref(j));/// add std:: to ref and cref
                      ^~~
p552.cpp:17:35: error: 'cref' is not a member of 'std'
   make_tuple(1, std::ref(i), std::cref(j));/// add std:: to ref and cref
                                   ^~~~
p552.cpp:17:35: note: suggested alternative: 'crend'
   make_tuple(1, std::ref(i), std::cref(j));/// add std:: to ref and cref
                                   ^~~~
                                   crend
p552.cpp:17:3: error: 'make_tuple' was not declared in this scope
   make_tuple(1, std::ref(i), std::cref(j));/// add std:: to ref and cref
   ^~~~~~~~~~
p552.cpp:17:3: note: suggested alternative:
In file included from p552.cpp:9:0:
/usr/local/Cellar/gcc/7.3.0_1/include/c++/7.3.0/tuple:1448:5: note:   'std::make_tuple'
     make_tuple(_Elements&&... __args)
     ^~~~~~~~~~
p552.cpp:19:8: error: declaration does not declare anything [-fpermissive]
   std::tuple<int, int&, const float&>;/// add std:: to tuple
        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
```

#検討事項(agenda)
clang++ -std=c++11, -std=c++17ではエラーなし、g++はコンパイルエラーの背景。
役に立つまたは意味のある出力

#参考資料(reference)

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

Clang/Clang++(LLVM) gcc/g++(GNU) コンパイラ警告等比較
https://qiita.com/kaizen_nagoya/items/9a82b958cc3aeef0403f

C++2003とC++2017でコンパイルエラーになるならない事例集
https://qiita.com/kaizen_nagoya/items/a13ea3823441c430edff

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

cpprefjpのdecltypeをコンパイル試験
https://qiita.com/kaizen_nagoya/items/090909af702f0d5d8a67

MISRA C++ 5-0-16
https://qiita.com/kaizen_nagoya/items/7df2d4e05db724752a74

C++ Templates Part1 BASICS Chapter 3. Class Templates 3.2 Use of Class Template Stack stack1test.cpp
https://qiita.com/kaizen_nagoya/items/cd5fc49106fad5a4e9ed


ISO/IEC TS 17961:2013 C Secure Coding Rules(1) All list(to be confirmed)
https://qiita.com/kaizen_nagoya/items/54e056195c4f11b850a1

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

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

'wchar.h' file not found で困った clang++ macOS
https://qiita.com/kaizen_nagoya/items/de15cd46d657517fac11

Open POSIX Test Suiteの使い方を調べはじめました
https://qiita.com/kaizen_nagoya/items/644d5e407f5faf96e6dc

MISRA-C 2012 Referenceに掲載している文献の入手可能性を確認
https://qiita.com/kaizen_nagoya/items/96dc8b125e462d5575bb

どうやって MISRA Example Suiteをコンパイルするか
https://qiita.com/kaizen_nagoya/items/fbdbff5ff696e2ca7f00

MISRA C まとめ #include <misra_c.h>
https://qiita.com/kaizen_nagoya/items/f1a79a7cbd281607c7c9

「C++完全理解ガイド」の同意できること上位10
https://qiita.com/kaizen_nagoya/items/aa5744e0c4a8618c7671

#文書履歴(document history)
ver. 0.10 初稿 20180430