runSofa crashes when creating a Sofa.Core.Controller object

[psomers3]

I've sucessfully compiled the latest sofa with the lastest SofaPython3 without errors on Windows 10 with Visual Studio 16. However, when I try and run the example "ControllerScene.py" with runSofa it crashes when calling the constructor for the base class in the init function. I've tried just simply creating a default Sofa.Core.Controller() object and it also crashes. Running the script directly with python does work without any problems because it doesn't need to create a Controller.

Am I possibly missing a plugin that the Controller needs?
The only thing I see from the output in terminal is a warning:
No python dir found in C:/Users/Somers/git/sofa-latest/build/install

I know the Python3 version is still heavily in development, but is this an issue that could be easily solved? What additional info would be helpful to help figure out the problem?

[jnbrunet]

Hey @psomers3 ,

We received some feedback not so long ago that, indeed, the controller is creating a segmentation fault on Windows upon its instantiation. Unfortunately, none of the developer that worked the most on SofaPython3 are on Windows, and this bug isn't present on MacOS or Linux.

I know the Python3 version is still heavily in development, but is this an issue that could be easily solved?

Easily fixed, maybe. Easily found, I don't think so. Someone with Windows will have to spend some time debugging it.

What additional info would be helpful to help figure out the problem?

I'll ping here @remibessard as he was the first to encounter this bug. Remi, did you finally found any hints on where this crash is coming from?

[psomers3]

Cool! Glad to have the feedback and know it's a windows thing and I'm not going crazy. :D
I don't mind taking a crack at finding the issue, and keeping my fingers crossed it is easy.

[psomers3]

If it helps, I've narrowed the problem to this point:
It crashes in the py::cast in py_shared_ptr. I believe the problem occurs with the std::forward call that occurs in pybind. When I add the line at 1759 in cast.h

auto forward_variable = std::forward<T>(value);

which is what is passed directly to the cast function, I get the following errors when compiling:

C:\Program Files\Python37\Lib\site-packages\pybind11\include\pybind11\cast.h(1759,1): error C2248: 'sofa::core::objectmodel::BaseObject::__vbaseDtor': cannot access protected member declared in class 'sofa::core::objectmodel::BaseObject' (compiling source file C:\Users\Somers\git\sofa-latest\applications\plugins\SofaPython3\bindings\Sofa\src\SofaPython3\Sofa\Core\Binding_BaseObject.cpp)

C:\Program Files\Python37\Lib\site-packages\pybind11\include\pybind11\cast.h(1759,18): error C2259: 'sofa::simulation::Node': cannot instantiate abstract class (compiling source file C:\Users\Somers\git\sofa-latest\applications\plugins\SofaPython3\bindings\Sofa\src\SofaPython3\Sofa\Core\Binding_Node.cpp)

C:\Program Files\Python37\Lib\site-packages\pybind11\include\pybind11\cast.h(1759,1): error C2248: 'sofa::simulation::Node::~Node': cannot access protected member declared in class 'sofa::simulation::Node' (compiling source file C:\Users\Somers\git\sofa-latest\applications\plugins\SofaPython3\bindings\Sofa\src\SofaPython3\Sofa\Core\Binding_Node.cpp)

Hope this is helpful. I'll keep digging as I can.

[jnbrunet]

Hey @psomers3 ,

Thank you for these hints. We haven't been able to look into it yet, but it should be soon: it is now in our target issues before the first official release of SofaPython3, which should be later this year (December) or at the very beginning (January) of next year.

If you found other hints since August, please let us know !

[psomers3]

That's good to hear! I haven't been able to debug it anymore and have since switched to using wsl2 for sofapython3. Would be nice to switch back to a single operating system though.