Clipper2 and CPP11

[AhsinChoudhry786]

What changes required to build clipper2 with C++11?

[sethhillbrand]

There are a lot of changes that would be required. Some are easy (change the use of auto in lambda expressions), some will require porting newer parts of the std library (std::numeric_limits, std::make_unique) and some are very difficult (managing the differences in move semantics)

You can change the CMakeLists.txt file to use

set(CMAKE_CXX_STANDARD 11)

and try to compile. Then slowly work through the bugs

[AhsinChoudhry786]

There are a lot of changes that would be required. Some are easy (change the use of auto in lambda expressions), some will require porting newer parts of the std library (std::numeric_limits, std::make_unique) and some are very difficult (managing the differences in move semantics)

You can change the CMakeLists.txt file to use

set(CMAKE_CXX_STANDARD 11)

and try to compile. Then slowly work through the bugs

Do you have a list of changes in a branch which I can use?

[sethhillbrand]

Do you have a list of changes in a branch which I can use?

No. I don't really see a use to that. If it is useful to you, you might try it. But I doubt that the access violation you are reporting has anything to do with the C++ grammar

[AhsinChoudhry786]

Ok

Do you have a list of changes in a branch which I can use?

No. I don't really see a use to that. If it is useful to you, you might try it. But I doubt that the access violation you are reporting has anything to do with the C++ grammar

Ok. But if I don’t pass a vector to a function, it doesn’t crash or give access violation

https://stackoverflow.com/questions/17885060/passing-reference-to-stl-vector-over-dll-boundary

[AhsinChoudhry786]

Any idea why it gives access violation when I call the DLL function from the application?

[reunanen]

ABI compatibility. You can basically pass POD only, and not std:: objects.

If you want to pass a vector, pass a pointer to int (or similar type), and the length.

Do not mix-and-match memory allocation and deallocation. If some memory is allocated on the Embarcadero side, free it there (and vice versa).

So build a so-called C API (and not C++). Depending on your application, it may be quite straightforward. Even though Clipper itself is C++, you should be able to wrap it behind a C API, which you can safely call from outside. This is a fairly common technique, generally used to overcome issues just like the one you are facing here.

And no, it's not about C++11 vs C++17. You can safely build Clipper using C++17, if you expose just a C API, which you then call from C++11.