unable to return shared_ptr from static function in pybind11

Question

I tried to bind a static function which returns a shared_ptr pointed to another class.

Here is the sample code

class Example {
  public:
    Example() {}
    ~Example() {}
};

class ABC {
  public:
    static std::shared_ptr<Example> get_example() {std::make_shared<Example();}
 };

void init_abc(py::module & m) {
  py::class_<Example>(m, "Example")
    .def(py::init<>());

  py::class_<ABC>(m, "ABC")
    .def_static("get_example", &ABC::get_example);
}

Here is the python side

example = my_module.ABC.get_example()

However, python side threw a segmentation fault.

Any idea?

Answer 1

There are some missing bits in your code like > . Here is working example:

class Example {
public:
    Example() {}
    ~Example() {}
};

class ABC {
public:
    static std::shared_ptr<Example> get_example() { return std::make_shared<Example>();}
};

Next, provide additional template argument shared_ptr<Example> in place where you wrap Example class:

py::class_<Example, std::shared_ptr<Example>>(m, "Example")
    .def(py::init<>());

py::class_<ABC>(m, "ABC")
    .def_static("get_example", &ABC::get_example);

This way shared_ptr<Example> will be handled properly.