Compiler that does not allow to determine the constructor generated by the compiler

I am trying to determine the constructor that the compiler automatically generates and results in a compilation error. Here is my code:

class myclass
 {
   public:
       void Test_Func()
       {}
 };
myclass::myclass()
{
}

The compiler does something extra for a simple class, as described above. Here is the error I received in the MSVC compiler:

"error C2600: 'myclass::myclass' : cannot define a compiler-generated special member function (must be declared in the class first)"