instrusive_list.cpp

template<typename Type, typename Tag = class default_tag>
struct list_mixin
{
    Type * prev = nullptr;
    Type * next = nullptr;
};

template<typename CRTP, typename... Tags>
struct list_mixins : list_mixin<CRTP, Tags>...
{
    template<typename T>
    auto & prev()
    {
        return static_cast<list_mixin<CRTP, T> &>(*this).prev;
    }
    
    template<typename T>
    auto & prev() const
    {
        return static_cast<const list_mixin<CRTP, T> &>(*this).prev;
    }
    
    template<typename T>
    auto & next()
    {
        return static_cast<list_mixin<CRTP, T> &>(*this).next;
    }

    template<typename T>
    auto & next() const
    {
        return static_cast<const list_mixin<CRTP, T> &>(*this).next;
    }
};
 
class thread : public list_mixins<thread, class all, class same_state>
{
};

#include <iostream>

int main()
{
    std::cout << thread{}.prev<class all>();
}