Passing opaque struct between functions/modules

[Sarath Kumar]

DMD v2.61; openSUSE 12.1

Source:
-------
libA.d:

module libA;

extern (C)
{
         struct Opaque;

         Opaque* getObject();

         void doSomething(Opaque *);
}
----------
libB.d:

module libB;

extern (C)
{
         struct Opaque;

         void doAction(Opaque *);
}
-----------
bug.d

import libA, libB;

int main(string[] args)
{
         auto opaque = libA.getObject();
         libA.doSomething(opaque); // this is okay
         libB.doAction(opaque);  // but this is not, compiler 
error here
         return 0;
}

When I compile the above files, I get the below error.
$ rdmd bug.d
bug.d(7): Error: function libB.doAction (Opaque*) is not callable 
using argument types (Opaque*)
bug.d(7): Error: cannot implicitly convert expression (opaque) of 
type Opaque* to Opaque*

If I do an explicit cast, libB.Opaque*, for opaque in line 7, 
bug.d, I get completely different set of errors.

$ rdmd bug.d
libB.d(5): Error: struct libB.Opaque unknown size
libB.d(5): Error: struct libB.Opaque no size yet for forward 
reference
libB.d(5): Error: struct libB.Opaque unknown size
libB.d(5): Error: struct libB.Opaque no size yet for forward 
reference
libA.d(5): Error: struct libA.Opaque unknown size
libA.d(5): Error: struct libA.Opaque no size yet for forward 
reference

Can someone please tell me the right way to pass an opaque object 
between module's functions.

--
Thanks,
Sarath