Clipper2 and cpp14

[petrasvestartas]

Hi,

Is there a possibility to change clipper2 library so that it compiles with cpp 14?

This is the error:

  In file included from src/frontend/src/3rd_party/Clipper2Lib/src/clipper.engine.cpp:17:
    In file included from src/frontend/src/3rd_party/Clipper2Lib/include/clipper2/clipper.engine.h:23:
    src/frontend/src/3rd_party/Clipper2Lib/include/clipper2/clipper.core.h:145:10: warning: constexpr if is a C++17 extension [-Wc++17-extensions]
          if constexpr (std::numeric_limits<T>::is_integer &&
             ^
    src/frontend/src/3rd_party/Clipper2Lib/include/clipper2/clipper.core.h:321:8: warning: constexpr if is a C++17 extension [-Wc++17-extensions]
        if constexpr (std::numeric_limits<T1>::is_integer &&
           ^
    src/frontend/src/3rd_party/Clipper2Lib/include/clipper2/clipper.core.h:466:8: warning: constexpr if is a C++17 extension [-Wc++17-extensions]
        if constexpr (std::numeric_limits<T1>::is_integer &&
           ^
    In file included from src/frontend/src/3rd_party/Clipper2Lib/src/clipper.engine.cpp:17:
    src/frontend/src/3rd_party/Clipper2Lib/include/clipper2/clipper.engine.h:349:53: error: member reference base type 'void' is not a structure or union
                            auto* result = childs_.emplace_back(std::move(p)).get();
                                           ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~
    src/frontend/src/3rd_party/Clipper2Lib/include/clipper2/clipper.engine.h:409:58: error: member reference base type 'void' is not a structure or union
                            PolyPathD* result = childs_.emplace_back(std::move(p)).get();
                                                ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~

[reunanen]

Maybe you can try something like this?

I mean locally, or in your own branch. It's 2023, and I think main should be allowed to require at least C++17.

[AhsinChoudhry786]

Trying to build the library using CPP 11 but getting errors

....\CPP\Clipper2Lib\include\clipper2/clipper.core.h(459,29): C++ error : 'auto' not allowed in function prototype
....\CPP\Clipper2Lib\include\clipper2/clipper.core.h(476,52): C++ error : no member named 'back_inserter' in namespace 'std'
....\CPP\Clipper2Lib\include\clipper2/clipper.core.h(485,54): C++ error : no member named 'back_inserter' in namespace 'std'
....\CPP\Clipper2Lib\include\clipper2/clipper.core.h(753,36): C++ error : use of undeclared identifier 'nearbyint'
DLL\CPP_DLL../../CPP/Clipper2Lib/include/clipper2/clipper.engine.h(349,52): C++ error : member reference base type 'void' is not a structure or union
CPP_DLL../../CPP/Clipper2Lib/include/clipper2/clipper.engine.h(370,23): C++ error : 'auto' not allowed in function prototype
CPP_DLL../../CPP/Clipper2Lib/include/clipper2/clipper.engine.h(409,57): C++ error : member reference base type 'void' is not a structure or union
CPP_DLL../../CPP/Clipper2Lib/include/clipper2/clipper.engine.h(430,23): C++ error : 'auto' not allowed in function prototype
CPP\Clipper2Lib\src\clipper.engine.cpp(135,48): C++ error : use of undeclared identifier 'nearbyint'
D:\Coda-Repos\app.surveyengine.x64\Libs\Clipper2Lib\CPP\Clipper2Lib\src\clipper.engine.cpp(587,17): C++ error : 'auto' not allowed in function prototype
c:\program files (x86)\embarcadero\studio\17.0\include\dinkumware64\numeric(13,9): C++ error : no matching function for call to object of type '<lambda at ./../CPP/Clipper2Lib/include/clipper2/clipper.engine.h:370:5>'
c:\program files (x86)\embarcadero\studio\17.0\include\dinkumware64\numeric(23,9): C++ error : in instantiation of function template specialization 'std::_Accumulate<const std::unique_ptr<Clipper2Lib::PolyPath64, std::default_deleteClipper2Lib::PolyPath64 > , double, <lambda at DLL\CPP_DLL../../CPP/Clipper2Lib/include/clipper2/clipper.engine.h:370:5> >' requested here
D:\Coda-Repos\app.surveyengine.x64\Libs\Clipper2Lib\DLL\CPP_DLL../../CPP/Clipper2Lib/include/clipper2/clipper.engine.h(368,15): C++ error : in instantiation of function template specialization 'std::accumulate<std::_Vector_const_iterator<std::_Vector_val<std::_Simple_types<std::unique_ptr<Clipper2Lib::PolyPath64, std::default_deleteClipper2Lib::PolyPath64 > > > >, double, <lambda at D:\Coda-Repos\app.surveyengine.x64\Libs\Clipper2Lib\DLL\CPP_DLL../../CPP/Clipper2Lib/include/clipper2/clipper.engine.h:370:5> >' requested here
D:\Coda-Repos\app.surveyengine.x64\Libs\Clipper2Lib\DLL\CPP_DLL../../CPP/Clipper2Lib/include/clipper2/clipper.engine.h(370,4): C++ error : candidate function not viable: no known conversion from 'const std::unique_ptr<Clipper2Lib::PolyPath64, std::default_deleteClipper2Lib::PolyPath64 >' to 'int &' for 2nd argument
D:\Coda-Repos\app.surveyengine.x64\Libs\Clipper2Lib\DLL\CPP_DLL../../CPP/Clipper2Lib/include/clipper2/clipper.engine.h(370,4): C++ error : conversion candidate of type 'void ()(double, int &)'
....\CPP\Clipper2Lib\include\clipper2/clipper.core.h(422,45): C++ error : use of undeclared identifier 'back_inserter'
....\CPP\Clipper2Lib\include\clipper2/clipper.core.h(433,11): C++ error : in instantiation of function template specialization 'Clipper2Lib::ScalePath<double, long long>' requested here
D:\Coda-Repos\app.surveyengine.x64\Libs\Clipper2Lib\DLL\CPP_DLL../../CPP/Clipper2Lib/include/clipper2/clipper.engine.h(410,22): C++ error : in instantiation of function template specialization 'Clipper2Lib::ScalePath<double, long long>' requested here
c:\program files (x86)\embarcadero\studio\17.0\include\dinkumware64\numeric(13,9): C++ error : no matching function for call to object of type '<lambda at D:\Coda-Repos\app.surveyengine.x64\Libs\Clipper2Lib\DLL\CPP_DLL../../CPP/Clipper2Lib/include/clipper2/clipper.engine.h:430:5>'
c:\program files (x86)\embarcadero\studio\17.0\include\dinkumware64\numeric(23,9): C++ error : in instantiation of function template specialization 'std::_Accumulate<const std::unique_ptr<Clipper2Lib::PolyPathD, std::default_deleteClipper2Lib::PolyPathD > , double, <lambda at D:\Coda-Repos\app.surveyengine.x64\Libs\Clipper2Lib\DLL\CPP_DLL../../CPP/Clipper2Lib/include/clipper2/clipper.engine.h:430:5> >' requested here
D:\Coda-Repos\app.surveyengine.x64\Libs\Clipper2Lib\DLL\CPP_DLL../../CPP/Clipper2Lib/include/clipper2/clipper.engine.h(428,15): C++ error : in instantiation of function template specialization 'std::accumulate<std::_Vector_const_iterator<std::_Vector_val<std::_Simple_types<std::unique_ptr<Clipper2Lib::PolyPathD, std::default_deleteClipper2Lib::PolyPathD > > > >, double, <lambda at D:\Coda-Repos\app.surveyengine.x64\Libs\Clipper2Lib\DLL\CPP_DLL../../CPP/Clipper2Lib/include/clipper2/clipper.engine.h:430:5> >' requested here
D:\Coda-Repos\app.surveyengine.x64\Libs\Clipper2Lib\DLL\CPP_DLL../../CPP/Clipper2Lib/include/clipper2/clipper.engine.h(430,4): C++ error : candidate function not viable: no known conversion from 'const std::unique_ptr<Clipper2Lib::PolyPathD, std::default_deleteClipper2Lib::PolyPathD >' to 'int &' for 2nd argument
D:\Coda-Repos\app.surveyengine.x64\Libs\Clipper2Lib\DLL\CPP_DLL../../CPP/Clipper2Lib/include/clipper2/clipper.engine.h(430,4): C++ error : conversion candidate of type 'void ()(double, int &)'
....\CPP\Clipper2Lib\include\clipper2/clipper.core.h(458,47): C++ error : use of undeclared identifier 'back_inserter'
....\CPP\Clipper2Lib\include\clipper2/clipper.core.h(468,11): C++ error : in instantiation of function template specialization 'Clipper2Lib::ScalePaths<long long, double>' requested here
D:\Coda-Repos\app.surveyengine.x64\Libs\Clipper2Lib\DLL\CPP_DLL../../CPP/Clipper2Lib/include/clipper2/clipper.engine.h(550,12): C++ error : in instantiation of function template specialization 'Clipper2Lib::ScalePaths<long long, double>' requested here
c:\program files (x86)\embarcadero\studio\17.0\include\dinkumware64\numeric(13,7): C++ error : assigning to 'int' from incompatible type 'void'
c:\program files (x86)\embarcadero\studio\17.0\include\dinkumware64\numeric(23,9): C++ error : in instantiation of function template specialization 'std::_Accumulate<const std::vector<Clipper2Lib::Point, std::allocator<Clipper2Lib::Point > > *, int, <lambda at D:\Coda-Repos\app.surveyengine.x64\Libs\Clipper2Lib\CPP\Clipper2Lib\src\clipper.engine.cpp:587:9> >' requested here
D:\Coda-Repos\app.surveyengine.x64\Libs\Clipper2Lib\CPP\Clipper2Lib\src\clipper.engine.cpp(586,11): C++ error : in instantiation of function template specialization 'std::accumulate<std::_Vector_const_iterator<std::_Vector_val<std::_Simple_types<std::vector<Clipper2Lib::Point, std::allocator<Clipper2Lib::Point > > > > >, int, <lambda at D:\Coda-Repos\app.surveyengine.x64\Libs\Clipper2Lib\CPP\Clipper2Lib\src\clipper.engine.cpp:587:9> >' requested here
D:\Coda-Repos\app.surveyengine.x64\Libs\Clipper2Lib\CPP\Clipper2Lib\src\clipper.offset.cpp(11,9): C++ error : 'clipper2/clipper.h' file not found
D:\Coda-Repos\app.surveyengine.x64\Libs\Clipper2Lib\CPP\Clipper2Lib\src\clipper.rectclip.cpp(11,9): C++ error : 'clipper2/clipper.h'

[reunanen]

With some more tweaks, now at least the tests are passing.