How to pass pointer to class member function to enzyme?

Consider following pointer to class member function
```C++
class MyFunctions{
...
void add_mul_const(double * a, double * b, double * out);
};

void __enzyme_autodiff(
void (MyFunctions::* )(double * , double * , double *),
int , double *, double *,
int, double *, double *,
int, double *, double *);

int main(){
...
void (MyFunctions::* f)(double * , double * , double *) = &MyFunctions::add_mul_const;
// FWD
(mf.*f)(a,b,out);

//Derivative
//__enzyme_autodiff(mf.*f, enzyme_dup, a, da, enzyme_dup, b, db, enzyme_dup, out, dout); ?
// __enzyme_autodiff(f, enzyme_dup, a, da, enzyme_dup, b, db, enzyme_dup, out, dout); ?

}
```

What will be correct format to pass pointer to class member function to Enzyme? Both of my attempts yielded errors
```
warning: Cannot cast __enzyme_autodiff primal argument 1, found i64 0, type i64 - to arg 0 %class.MyFunctions* [-Wpass-failed=enzyme]
int main(){
^
error: :0:0: EnzymeFailure when replacing __enzyme_autodiff calls in main
1 warning and 1 error generated.
```
and

```
error: reference to non-static member function must be called
__enzyme_autodiff(mf.*f, enzyme_const, a, enzyme_dup, b, db, enzyme_dup, out, dout);

```

Also is there anyway I can calculate derivative functions of these memeber functions without having to instantiate the class first?