Hi,
Trying to do something like this:

struct A
{
	sigc::signal<void(int, float) > sign;
};

struct B
{
	B (A & a)
	{
		a.sign.connect(sigc::bind<0>(sigc::mem_fun(*this, &B::func), true));
	}

	void func(bool b, int i, float f)
	{
	}
};

Got the error:

'sigc::bind_functor<0,T_functor,bool>::bound_': cannot access private member declared in class 'sigc::bind_functor<0,T_functor,bool>'

Visual Studio 2017 (all updates installed)
libsig version: 3.0
C++: ISO C++17 Standard (/std:c++17)