10.3 Import declaration [module.import] C++N4910:2022 (132) p251.cpp

# はじめに(Introduction)

N4910  Working Draft, Standard for Programming Language C++

http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2022/n4910.pdf

n4910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。

 <この項は書きかけです。順次追記します。>

## 背景(back ground)
C/C++でコンパイルエラーが出ると、途方にくれることがしばしばあります。
何回かに１回は、該当するエラーが検索できます。
ただ、条件が違っていて、そこでの修正方法では目的を達成しないこともしばしばです。いろいろな条件のコンパイルエラーとその対応方法について、広く記録することによって、いつか同じエラーに遭遇した時にやくに立つことを目指しています。

この半年の間で、三度、自分のネットでの記録に助けられたことがあります。
また過去に解決できなかった記録を１０種類以上、最近になって解決できたことがあります。それは、主に次の３つの情報に基づいています。

https://stackoverflow.com
https://cpprefjp.github.io
http://ja.cppreference.com/

また
https://researchmap.jp/joub9b3my-1797580/#_1797580
に記載したサイトのお世話になっています。

## 作業方針(sequence)
Clang++では-std=c++03, C++2bの2種類
g++では-std=c++03, c++2bの２種類
でコンパイルし、

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++N4910:2022 Standard Working Draft on ISO/IEC 14882(0) sample code compile list  

https://qiita.com/kaizen_nagoya/items/fc957ddddd402004bb91

### C++N4741, 2018 Standard Working Draft on ISO/IEC 14882 sample code compile list
https://qiita.com/kaizen_nagoya/items/3294c014044550896010

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

### C++N3242, 2011 sample code compile list on clang++ and g++
https://qiita.com/kaizen_nagoya/items/685b5c1a2c17c1bf1318

## 編纂器(Compiler)
### clang++ --version
> Debian clang version 14.0.5-++20220610033153+c12386ae247c-1~exp1~20220610153237.151
Target: x86_64-pc-linux-gnu, Thread model: posix, InstalledDir: /usr/bin

### g++- --version
> g++ (GCC) 12.1.0  Copyright (C) 2022 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

# 10.3 Import declaration [module.import] C++N4910:2022 (132) p251.cpp

## 算譜(source code)

```c++:p251.cpp
// C++N4910 Committee Draft, Standard for Programming Language C++
// http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2022/n4910.pdf
const char * n4910 = "10.3 Import declaration [module.import] C++N4910:2022 (132) p251.cpp";
// Debian clang version 14.0.5-++20220610033153+c12386ae247c-
// g++ (GCC) 12.1.0 Copyright (C) 2022 Free Software Foundation, Inc.
// Edited by Dr. Ogawa Kiyoshi. Compile procedure and results record.
// C++N4910:2022 Standard Working Draft on ISO/IEC 14882(0) sample code compile list
// https://qiita.com/kaizen_nagoya/items/fc957ddddd402004bb91

#include <iostream>
#include <cstdio>
#include <cstdlib> 
#include <cstring>
#include <cassert>
#include <coroutine>
#include <vector>
#include <complex>
#include <map>
#include <atomic>
#include <unordered_map>

using namespace std;

// Example 1  
// Translation unit #1:
     module M:Part;
/* Translation unit #2:
export module M;
export import :Part;
*/
// error: exported partition :Part is an implementation unit
// [Example 2:
module M;
import M; // error: cannot import M in its own unit
// [Example 3: Interface unit of M1:
  export module M1;
  import M2;
Interface unit of M2: export module M2;
import M3;
Interface unit of M3: export module M3;
import M1;
// error: cyclic interface dependency M3 → M1 → M2 → M3
int main(){
  cout  <<  n4910 << endl;
  return EXIT_SUCCESS;
}
```

## Script

```bash:clgc.sh
#!/bin/sh
rm $1l
rm $1g
echo "$ clang++ $1.cpp -std=03 -o $1l -I. -Wall" 
clang++ $1.cpp -std=c++03 -o $1l -I. -Wall
if [  -e $1l ]; then
./$1l 
fi
rm $1l
echo "$ clang++ $1.cpp -std=2b -o $1l -I. -Wall"
clang++ $1.cpp -std=c++2b -o $1l -I. -Wall
if [  -e $1l ]; then
./$1l
fi
echo "\r"
echo "$ g++ $1.cpp -std=03 -o $1g -I. -Wall"
g++ $1.cpp -std=c++03 -o $1g -I. -Wall
if [ -e $1g ]; then
./$1g
fi
rm $1g
echo "\r"
echo "$ g++ $1.cpp -std=2b -o $1g -I. -Wall"
g++ $1.cpp -std=c++2b -o $1g -I. -Wall
if [ -e $1g ]; then
./$1g 
fi
```
## 編纂・実行結果(compile and go)

```ubuntu:bash
# clang++ -c p251.cpp p251a.cpp p251b.cpp p251c.cpp -std=c++2b  -I. -Wall -fmodule-file=p251
p251.cpp:1:9: error: sorry, module partitions are not yet supported
module M:Part;
        ^~~~~
p251.cpp:1:1: error: definition of module 'M' is not available; use -fmodule-file= to specify path to precompiled module interface
module M:Part;
^
In file included from p251.cpp:11:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/iostream:39:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/ostream:38:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/ios:39:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/exception:147:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/bits/exception_ptr.h:39:
/usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/typeinfo:88:9: error: declaration of 'type_info' in the global module follows declaration in module M
  class type_info
        ^
/usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/bits/cxxabi_init_exception.h:52:9: note: previous declaration is here
  class type_info;
        ^
In file included from p251.cpp:11:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/iostream:39:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/ostream:38:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/ios:39:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/exception:147:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/bits/exception_ptr.h:40:
/usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/new:126:26: error: declaration of 'operator new' in the global module follows declaration in module M
_GLIBCXX_NODISCARD void* operator new(std::size_t) _GLIBCXX_THROW (std::bad_alloc)
                         ^
note: previous declaration is here
/usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/new:128:26: error: declaration of 'operator new[]' in the global module follows declaration in module M
_GLIBCXX_NODISCARD void* operator new[](std::size_t) _GLIBCXX_THROW (std::bad_alloc)
                         ^
note: previous declaration is here
/usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/new:130:6: error: declaration of 'operator delete' in the global module follows declaration in module M
void operator delete(void*) _GLIBCXX_USE_NOEXCEPT
     ^
note: previous declaration is here
/usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/new:132:6: error: declaration of 'operator delete[]' in the global module follows declaration in module M
void operator delete[](void*) _GLIBCXX_USE_NOEXCEPT
     ^
note: previous declaration is here
/usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/new:149:26: error: declaration of 'operator new' in the global module follows declaration in module M
_GLIBCXX_NODISCARD void* operator new(std::size_t, std::align_val_t)
                         ^
note: previous declaration is here
/usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/new:153:6: error: declaration of 'operator delete' in the global module follows declaration in module M
void operator delete(void*, std::align_val_t)
     ^
note: previous declaration is here
/usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/new:157:26: error: declaration of 'operator new[]' in the global module follows declaration in module M
_GLIBCXX_NODISCARD void* operator new[](std::size_t, std::align_val_t)
                         ^
note: previous declaration is here
/usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/new:161:6: error: declaration of 'operator delete[]' in the global module follows declaration in module M
void operator delete[](void*, std::align_val_t)
     ^
note: previous declaration is here
In file included from p251.cpp:11:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/iostream:39:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/ostream:38:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/ios:40:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/bits/char_traits.h:39:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/bits/stl_algobase.h:65:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/bits/stl_iterator_base_types.h:71:
/usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/bits/iterator_concepts.h:52:12: error: declaration of 'iterator_traits' in module M follows declaration in the global module
    struct iterator_traits;
           ^
/usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/bits/cpp_type_traits.h:423:29: note: previous declaration is here
  template<typename> struct iterator_traits;
                            ^
In file included from p251.cpp:11:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/iostream:39:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/ostream:38:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/ios:42:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/bits/ios_base.h:39:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/ext/atomicity.h:35:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/x86_64-linux-gnu/c++/10/bits/gthr.h:148:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:35:
In file included from /usr/include/pthread.h:22:
/usr/include/sched.h:54:56: error: declaration of 'sched_param' in the global module follows declaration in module M
extern int sched_setparam (__pid_t __pid, const struct sched_param *__param)
                                                       ^
/usr/include/x86_64-linux-gnu/bits/types/struct_sched_param.h:23:8: note: previous declaration is here
struct sched_param
       ^
In file included from p251.cpp:11:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/iostream:39:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/ostream:38:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/ios:42:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/bits/ios_base.h:39:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/ext/atomicity.h:35:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/x86_64-linux-gnu/c++/10/bits/gthr.h:148:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:35:
In file included from /usr/include/pthread.h:22:
/usr/include/sched.h:58:50: error: declaration of 'sched_param' in the global module follows declaration in module M
extern int sched_getparam (__pid_t __pid, struct sched_param *__param) __THROW;
                                                 ^
/usr/include/x86_64-linux-gnu/bits/types/struct_sched_param.h:23:8: note: previous declaration is here
struct sched_param
       ^
In file included from p251.cpp:11:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/iostream:39:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/ostream:38:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/ios:42:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/bits/ios_base.h:39:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/ext/atomicity.h:35:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/x86_64-linux-gnu/c++/10/bits/gthr.h:148:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:35:
In file included from /usr/include/pthread.h:22:
/usr/include/sched.h:62:24: error: declaration of 'sched_param' in the global module follows declaration in module M
                               const struct sched_param *__param) __THROW;
                                            ^
/usr/include/x86_64-linux-gnu/bits/types/struct_sched_param.h:23:8: note: previous declaration is here
struct sched_param
       ^
In file included from p251.cpp:11:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/iostream:39:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/ostream:38:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/ios:42:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/bits/ios_base.h:39:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/ext/atomicity.h:35:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/x86_64-linux-gnu/c++/10/bits/gthr.h:148:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:35:
In file included from /usr/include/pthread.h:22:
/usr/include/sched.h:77:57: error: declaration of 'timespec' in the global module follows declaration in module M
extern int sched_rr_get_interval (__pid_t __pid, struct timespec *__t) __THROW;
                                                        ^
/usr/include/x86_64-linux-gnu/bits/types/struct_timespec.h:10:8: note: previous declaration is here
struct timespec
       ^
In file included from p251.cpp:11:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/iostream:39:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/ostream:38:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/ios:42:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/bits/ios_base.h:39:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/ext/atomicity.h:35:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/x86_64-linux-gnu/c++/10/bits/gthr.h:148:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:35:
In file included from /usr/include/pthread.h:23:
In file included from /usr/include/time.h:33:
/usr/include/x86_64-linux-gnu/bits/time.h:78:58: error: declaration of 'timex' in the global module follows declaration in module M
extern int clock_adjtime (__clockid_t __clock_id, struct timex *__utx) __THROW;
                                                         ^
/usr/include/x86_64-linux-gnu/bits/timex.h:26:8: note: previous declaration is here
struct timex
       ^
In file included from p251.cpp:11:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/iostream:39:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/ostream:38:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/ios:42:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/bits/ios_base.h:39:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/ext/atomicity.h:35:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/x86_64-linux-gnu/c++/10/bits/gthr.h:148:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:35:
In file included from /usr/include/pthread.h:23:
In file included from /usr/include/time.h:39:
/usr/include/x86_64-linux-gnu/bits/types/struct_tm.h:7:8: error: declaration of 'tm' in module M follows declaration in the global module
struct tm
       ^
/usr/include/wchar.h:83:8: note: previous declaration is here
struct tm;
       ^
In file included from p251.cpp:11:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/iostream:39:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/ostream:38:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/ios:42:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/bits/ios_base.h:39:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/ext/atomicity.h:35:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/x86_64-linux-gnu/c++/10/bits/gthr.h:148:
In file included from /usr/bin/../lib/gcc/x86_64-linux-gnu/10/../../../../include/x86_64-linux-gnu/c++/10/bits/gthr-default.h:35:
In file included from /usr/include/pthread.h:23:
/usr/include/time.h:82:30: error: declaration of 'tm' in the global module follows declaration in module M
extern time_t mktime (struct tm *__tp) __THROW;
                             ^
/usr/include/x86_64-linux-gnu/bits/types/struct_tm.h:7:8: note: previous declaration is here
struct tm
       ^
fatal error: too many errors emitted, stopping now [-ferror-limit=]
20 errors generated.
p251a.cpp:9:15: error: sorry, module partitions are not yet supported
export import :Part;
              ^~~~~
1 error generated.
p251b.cpp:1:1: error: definition of module 'M' is not available; use -fmodule-file= to specify path to precompiled module interface
module M;
^
1 error generated.
p251c.cpp:2:8: fatal error: module 'M2' not found
import M2;
~~~~~~~^~
1 error generated.

# g++ -c p251.cpp p251a.cpp p251b.cpp p251c.cpp p-std=2b  -I. -Wall -fmodules-ts
In file included from p251.cpp:16:
/usr/local/include/c++/12.1.0/coroutine:361:2: error: #error "the coroutine header requires -fcoroutines"
  361 | #error "the coroutine header requires -fcoroutines"
      |  ^~~~~
In file included from /usr/local/include/c++/12.1.0/iostream:38,
                 from p251.cpp:11:
/usr/local/include/c++/12.1.0/x86_64-linux-gnu/bits/c++config.h: In function 'void std::__terminate()':
/usr/local/include/c++/12.1.0/x86_64-linux-gnu/bits/c++config.h:311:10: error: block-scope extern declaration 'void std::terminate()' not permitted in module purview
  311 |     void terminate() _GLIBCXX_USE_NOEXCEPT __attribute__ ((__noreturn__));
      |          ^~~~~~~~~
In file included from /usr/local/include/c++/12.1.0/bits/exception_ptr.h:40,
                 from /usr/local/include/c++/12.1.0/exception:168,
                 from /usr/local/include/c++/12.1.0/ios:39,
                 from /usr/local/include/c++/12.1.0/ostream:38,
                 from /usr/local/include/c++/12.1.0/iostream:39:
/usr/local/include/c++/12.1.0/new: At global scope:
/usr/local/include/c++/12.1.0/new:89:27: error: cannot define 'enum class std::align_val_t' in different module
   89 |   enum class align_val_t: size_t {};
      |                           ^~~~~~
<built-in>: note: declared here
/usr/local/include/c++/12.1.0/new:89: confused by earlier errors, bailing out
In module imported at p251a.cpp:9:8:
M:Part: error: failed to read compiled module: No such file or directory
M:Part: note: compiled module file is 'gcm.cache/M-Part.gcm'
M:Part: note: imports must be built before being imported
M:Part: fatal error: returning to the gate for a mechanical issue
compilation terminated.
In module imported at p251b.cpp:2:1:
M: error: failed to read compiled module: No such file or directory
M: note: compiled module file is 'gcm.cache/M.gcm'
M: note: imports must be built before being imported
M: fatal error: returning to the gate for a mechanical issue
compilation terminated.
In module imported at p251c.cpp:2:1:
M2: error: failed to read compiled module: No such file or directory
M2: note: compiled module file is 'gcm.cache/M2.gcm'
M2: note: imports must be built before being imported
M2: fatal error: returning to the gate for a mechanical issue
compilation terminated.
```

## 検討事項(agenda)
コンパイルエラーの理由を解説する。

<|--コンパイルエラーを取るか、コンパイルエラーの理由を解説する。-->

# 参考資料(reference)

cpprefjp - C++日本語リファレンス

https://cpprefjp.github.io/

コンパイラの実装状況

https://cpprefjp.github.io/implementation-status.html


typedef は C++11 ではオワコン

https://qiita.com/Linda_pp/items/44a67c64c14cba00eef1

C99からC++14を駆け抜けるC++講座

https://qiita.com/yumetodo/items/e49a673afd9a3ecb81a8

## 自己参照(self reference)

C++ Error Message Collection(1)does not name a type, 11 articles

https://qiita.com/kaizen_nagoya/items/acb9f1a9b5aad6df06bd

dockerにclang

https://qiita.com/kaizen_nagoya/items/8829ffeee397eda50e80

docker gnu(gcc/g++) and llvm(clang/clang++)

https://qiita.com/drafts/059874ea39c4de64c0f7

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

Compare the contents of C++N4910:2022, C++N4741:2018 and C++N4606:2015

https://qiita.com/kaizen_nagoya/items/483246d40f98abff7ded

C++ sample list

https://qiita.com/kaizen_nagoya/items/54ad75b73825b7c04f86


clang++, g++コンパイルエラー方針の違いの例

https://qiita.com/kaizen_nagoya/items/ea6e5009fe126d270a82

astyle 使ってみた

https://qiita.com/kaizen_nagoya/items/3c9a87a781d53a1a23f3

C++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


 ＜この記事は個人の過去の経験に基づく個人の感想です。現在所属する組織、業務とは関係がありません。＞

# 文書履歴(document history)
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