[BUG]: Cannot wrap class with virtual inheritance and shared_ptr holder?

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Problem description

The code below throws an error

pybind11.h(1792,1): error C2664: 'std::shared_ptr::shared_ptr(std::nullptr_t) noexcept': cannot convert argument 1 from 'V *' to 'std::nullptr_t

This does not seem expected... This only does it for the bindings of B, not A.

This is different from the other issues I found since in this case the class is actually polymorphic and does inherit from enable_shared_from_this.

Reproducible example code

#include <memory>

#include <pybind11/pybind11.h>

namespace py = pybind11;

class A : public std::enable_shared_from_this<A> {
public:
    virtual ~A() {}
};

class B : public virtual A {
protected:
    ~B() {}
};

PYBIND11_MODULE(module, m) {
    py::class_<A, std::shared_ptr<A>>(m, "A");
    py::class_<B, std::shared_ptr<B>, A>(m, "B");
}

Start with the reproducible C++ example and inspect pybind11.h around line 1792, where the shared_ptr conversion error is reported. Confirm the failure when binding B with virtual inheritance and its shared_ptr holder; done means the example binds successfully without the reported compiler error.