N4606 Working Draft 2016, ISO/IEC 14882, C++ standard(67)7.1.3 The typedef specifier [dcl.typedef]

はじめに

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

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。

list

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

Compiler

clang++ --version

clang version 6.0.0 (tags/RELEASE_600/final)

g++-7 --version

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

(67)7.1.3 The typedef specifier [dcl.typedef]

p158
```c++:p158.cpp
// N4606 Committee Draft, Standard for Programming Language C++
// http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/n4606.pdf

define msg "p158.cpp(67)7.1.3 The typedef specifier [dcl.typedef]"

include

typedef int MILES, KLICKSP;
MILES distance;
extern KLICKSP metricp;
using handler_t = void ()(int);
extern handler_t ignore;
extern void (*ignore)(int); // redeclare ignore
using cell = pair<void, cell
>; // ill-formed
typedef struct s { /* ... / } s;
typedef int I;
typedef int I;
typedef I I;
struct S {
typedef struct A { } A; // OK
typedef struct B B; // OK
typedef A A; // error
};
struct S;
typedef struct S S;
int main() {
struct S
p; // OK
std::cout<< msg << std::endl;
return EXIT_SUCCESS;
}
struct S { }; // OK
class complex { /* ... / };
typedef int complex; // error: redefinition
typedef int complex;
class complex { /
... */ }; // error: redefinition
struct S {
S();
~S();
};
typedef struct S T;
S a = T(); // OK
struct T * p; // error
typedef struct { } *ps, S; // S is the class name for linkage purposes
```

$ ./cppgl17.sh p158
$ clang++ p158.cpp
clang-6.0: error: no such file or directory: 'p158.cpp'
clang-6.0: error: no input files

$ g++-7 p158.cpp
g++-7: error: p158.cpp: No such file or directory
g++-7: fatal error: no input files
compilation terminated.
OgawaKiyoshi-no-MacBook-Pro:cpp ogawakiyoshi$ mv p158.pp p158.cpp
OgawaKiyoshi-no-MacBook-Pro:cpp ogawakiyoshi$ ./cppgl17.sh p158
$ clang++ p158.cpp
p158.cpp:10:24: error: function cannot return function type 'void (int)'
using handler_t = void ()(int);
                       ^
p158.cpp:11:8: error: unknown type name 'handler_t'
extern handler_t ignore;
       ^
p158.cpp:13:14: error: no template named 'pair'; did you mean 'std::pair'?
using cell = pair<void, cell*>; // ill-formed
             ^~~~
             std::pair
/usr/local/Cellar/llvm/6.0.0/include/c++/v1/utility:312:29: note: 'std::pair' declared here
struct _LIBCPP_TEMPLATE_VIS pair
                            ^
p158.cpp:13:25: error: use of undeclared identifier 'cell'
using cell = pair<void, cell*>; // ill-formed
                        ^
p158.cpp:13:30: error: expected expression
using cell = pair<void, cell*>; // ill-formed
                             ^
p158.cpp:21:13: error: redefinition of 'A'
  typedef A A; // error
            ^
p158.cpp:19:24: note: previous definition is here
  typedef struct A { } A; // OK
                       ^
p158.cpp:30:8: error: redefinition of 'S'
struct S { }; // OK
       ^
p158.cpp:18:8: note: previous definition is here
struct S {
       ^
p158.cpp:32:13: error: typedef redefinition with different types ('int' vs 'complex')
typedef int complex; // error: redefinition
            ^
p158.cpp:31:7: note: previous definition is here
class complex { /* ... */ };
      ^
p158.cpp:33:13: error: typedef redefinition with different types ('int' vs 'complex')
typedef int complex;
            ^
p158.cpp:31:7: note: previous definition is here
class complex { /* ... */ };
      ^
p158.cpp:34:7: error: redefinition of 'complex'
class complex { /* ... */ }; // error: redefinition
      ^
p158.cpp:31:7: note: previous definition is here
class complex { /* ... */ };
      ^
p158.cpp:35:8: error: redefinition of 'S'
struct S {
       ^
p158.cpp:18:8: note: previous definition is here
struct S {
       ^
p158.cpp:41:8: error: typedef 'T' cannot be referenced with a struct specifier
struct T * p; // error
       ^
p158.cpp:39:18: note: declared here
typedef struct S T;
                 ^
p158.cpp:42:25: error: typedef redefinition with different types ('struct S' vs 'struct S')
typedef struct { } *ps, S; // S is the class name for linkage purposes
                        ^
p158.cpp:24:18: note: previous definition is here
typedef struct S S;
                 ^
13 errors generated.

$ g++-7 p158.cpp
p158.cpp:10:30: error: 'type name' declared as function returning a function
 using handler_t = void ()(int);
                              ^
p158.cpp:11:8: error: 'handler_t' does not name a type
 extern handler_t ignore;
        ^~~~~~~~~
p158.cpp:13:14: error: 'pair' does not name a type; did you mean 'wait'?
 using cell = pair<void, cell*>; // ill-formed
              ^~~~
              wait
p158.cpp:21:13: error: redeclaration of 'typedef S::A S::A'
   typedef A A; // error
             ^
p158.cpp:19:24: note: previous declaration 'typedef struct S::A S::A'
   typedef struct A { } A; // OK
                        ^
p158.cpp:30:8: error: redefinition of 'struct S'
 struct S { }; // OK
        ^
p158.cpp:18:8: note: previous definition of 'struct S'
 struct S {
        ^
p158.cpp:32:13: error: conflicting declaration 'typedef int complex'
 typedef int complex; // error: redefinition
             ^~~~~~~
p158.cpp:31:7: note: previous declaration as 'class complex'
 class complex { /* ... */ };
       ^~~~~~~
p158.cpp:33:13: error: conflicting declaration 'typedef int complex'
 typedef int complex;
             ^~~~~~~
p158.cpp:31:7: note: previous declaration as 'class complex'
 class complex { /* ... */ };
       ^~~~~~~
p158.cpp:34:7: error: redefinition of 'class complex'
 class complex { /* ... */ }; // error: redefinition
       ^~~~~~~
p158.cpp:31:7: note: previous definition of 'class complex'
 class complex { /* ... */ };
       ^~~~~~~
p158.cpp:35:8: error: redefinition of 'struct S'
 struct S {
        ^
p158.cpp:18:8: note: previous definition of 'struct S'
 struct S {
        ^
p158.cpp:41:8: error: using typedef-name 'T' after 'struct'
 struct T * p; // error
        ^
p158.cpp:39:18: note: 'T' has a previous declaration here
 typedef struct S T;
                  ^
p158.cpp:42:25: error: conflicting declaration 'typedef struct S S'
 typedef struct { } *ps, S; // S is the class name for linkage purposes
                         ^
p158.cpp:24:18: note: previous declaration as 'typedef struct S S'
 typedef struct S S;
                  ^

検討事項

コンパイルエラーの出ない修正。

参考資料

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

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https://qiita.com/kaizen_nagoya/items/9a82b958cc3aeef0403f

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

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
https://qiita.com/kaizen_nagoya/items/f1a79a7cbd281607c7c9

文書履歴

0.10 初稿 2080417

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