Pybind11 + Autodiff::VectorXvar gives compiltion error

[ipcamit]

When I try to mix <pybind11/eigen.h> and <autodiff/reverse/var/eigen.h> I get the following error, however it works fine with <autodiff/forward/real/eigen.h>. Is there a known way to mix reverse with pybind11/eigen ?

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Error:

In file included from /opt/mambaforge/mambaforge/envs/colabfit/include/pybind11/eigen/matrix.h:12,
                 from /opt/mambaforge/mambaforge/envs/colabfit/include/pybind11/eigen.h:12,
                 from /home/amit/Tutorials/autodiff/example_pybind.cpp:6:
/opt/mambaforge/mambaforge/envs/colabfit/include/pybind11/numpy.h: In instantiation of ‘struct pybind11::detail::npy_format_descriptor<autodiff::detail::Variable<double>, void>’:
/opt/mambaforge/mambaforge/envs/colabfit/include/pybind11/eigen/matrix.h:224:40:   required from ‘constexpr const auto pybind11::detail::EigenProps<Eigen::Matrix<autodiff::detail::Variable<double>, -1, 1, 0, -1, 1> >::descriptor’
/opt/mambaforge/mambaforge/envs/colabfit/include/pybind11/eigen/matrix.h:388:27:   required from ‘constexpr const auto pybind11::detail::type_caster<Eigen::Matrix<autodiff::detail::Variable<double>, -1, 1, 0, -1, 1>, void>::name’
/opt/mambaforge/mambaforge/envs/colabfit/include/pybind11/cast.h:1404:56:   required from ‘constexpr const auto pybind11::detail::argument_loader<MyFunc*, Eigen::Matrix<autodiff::detail::Variable<double>, -1, 1, 0, -1, 1>&, Eigen::Matrix<autodiff::detail::Variable<double>, -1, 1, 0, -1, 1>&>::arg_names’
/opt/mambaforge/mambaforge/envs/colabfit/include/pybind11/pybind11.h:291:31:   required from ‘void pybind11::cpp_function::initialize(Func&&, Return (*)(Args ...), const Extra& ...) [with Func = pybind11::cpp_function::cpp_function(Return (Class::*)(Arg ...), const Extra& ...) [with Return = void; Class = MyFunc; Arg = {Eigen::Matrix<autodiff::detail::Variable<double>, -1, 1, 0, -1, 1>&, Eigen::Matrix<autodiff::detail::Variable<double>, -1, 1, 0, -1, 1>&}; Extra = {pybind11::name, pybind11::is_method, pybind11::sibling}]::<lambda(MyFunc*, Eigen::Matrix<autodiff::detail::Variable<double>, -1, 1, 0, -1, 1>&, Eigen::Matrix<autodiff::detail::Variable<double>, -1, 1, 0, -1, 1>&)>; Return = void; Args = {MyFunc*, Eigen::Matrix<autodiff::detail::Variable<double>, -1, 1, 0, -1, 1>&, Eigen::Matrix<autodiff::detail::Variable<double>, -1, 1, 0, -1, 1>&}; Extra = {pybind11::name, pybind11::is_method, pybind11::sibling}]’
/opt/mambaforge/mambaforge/envs/colabfit/include/pybind11/pybind11.h:109:9:   required from ‘pybind11::cpp_function::cpp_function(Return (Class::*)(Arg ...), const Extra& ...) [with Return = void; Class = MyFunc; Arg = {Eigen::Matrix<autodiff::detail::Variable<double>, -1, 1, 0, -1, 1>&, Eigen::Matrix<autodiff::detail::Variable<double>, -1, 1, 0, -1, 1>&}; Extra = {pybind11::name, pybind11::is_method, pybind11::sibling}]’
/opt/mambaforge/mambaforge/envs/colabfit/include/pybind11/pybind11.h:1568:22:   required from ‘pybind11::class_<type_, options>& pybind11::class_<type_, options>::def(const char*, Func&&, const Extra& ...) [with Func = void (MyFunc::*)(Eigen::Matrix<autodiff::detail::Variable<double>, -1, 1, 0, -1, 1>&, Eigen::Matrix<autodiff::detail::Variable<double>, -1, 1, 0, -1, 1>&); Extra = {}; type_ = MyFunc; options = {PyFunc}]’
/home/amit/Tutorials/autodiff/example_pybind.cpp:49:29:   required from here
/opt/mambaforge/mambaforge/envs/colabfit/include/pybind11/numpy.h:1420:37: error: static assertion failed: Attempt to use a non-POD or unimplemented POD type as a numpy dtype
 1420 |     static_assert(is_pod_struct<T>::value,
      |                                     ^~~~~
make[2]: *** [CMakeFiles/example_pybind11.dir/build.make:63: CMakeFiles/exam

C++ file:

// C++ includes
#include <iostream>

// Pybind11 includes
#include <pybind11/pybind11.h>
#include <pybind11/eigen.h>
#include <pybind11/stl.h>
#include <pybind11/numpy.h>

// autodiff include
// << This does not compile >>
#include <autodiff/reverse/var.hpp>
#include <autodiff/reverse/var/eigen.hpp>
typedef autodiff::VectorXvar  vector_kind;

// << This compiles >>
//#include <autodiff/forward/real.hpp>
//#include <autodiff/forward/real/eigen.hpp>
//typedef autodiff::VectorXreal  vector_kind;

using namespace autodiff;

// Base virtual class
class MyFunc {
public:
    virtual void f(vector_kind& x, vector_kind& y) = 0;};

// Concrete class
class MyFunc1 : public MyFunc {
public:
    void f(vector_kind& x, vector_kind& y) override { y = 2 * x;}};

// Pybind11 Trampoline
class PyFunc : public MyFunc {
    public:
        using MyFunc::MyFunc;

        void f(vector_kind& x, vector_kind& y) override {
            PYBIND11_OVERLOAD_PURE(void, MyFunc, f, x, y);
        }
};

PYBIND11_MODULE(example_pybind, m) {
    pybind11::class_<MyFunc, PyFunc>(m, "MyFunc")
        .def(pybind11::init<>())
        .def("f", &MyFunc::f);
}

CMAKE file:

cmake_minimum_required(VERSION 3.15)

project(example)
set(CMAKE_CXX_STANDARD 17)
include_directories(autodiff_includes)
find_package(PythonInterp REQUIRED)
find_package(PythonLibs REQUIRED)
include_directories(${PYTHON_INCLUDE_DIRS})

# PYBIND11
find_package(pybind11 REQUIRED)

pybind11_add_module(example_pybind11 example_pybind.cpp)