Class make_default_obj

test/helpers.h:198–205

Default construct object to avoid bug in clang error: default member initializer for 'y' needed within definition of enclosing class 'X' outside of member functions see https://stackoverflow.com/questions/53408962

// error: default member initializer for 'y' needed within definition of enclosing class 'X' outside of member functions
// see https://stackoverflow.com/questions/53408962
struct make_default_obj
{
    template<class T>
    operator T() const // NOLINT
    {
        return T{};
    }
};

inline std::string filter_valueflow(const std::string& s) {
    bool filtered = false;