GCC Bugzilla Bug 13420

On Cygwin (1.5.5) and using g++ 3.3.1 ("g++ (GCC) 3.3.1 (cygming special)") 

Using the 3 files below,

$ cat AA1.h
#pragma interface

#include "AA2.h"

class AA1 {
public:
  void g(){
    std::ostringstream os;
  }
};

$ cat AA2.h
#pragma interface

#include <sstream>
#include <iostream>

class AA2 {
 public:
  void f(std::ostringstream os) {
    os.str();
  }
};

$ cat BB.cpp
#include "AA1.h"

#pragma implementation "AA1.h"
#pragma implementation "AA2.h"

int myi;

A compilation results in two bogus undefined
symbols.
$ g++ -c BB.cpp  ; nm BB.o | grep ' U'
         U __GLOBAL__D_myi
         U __GLOBAL__I_myi

It works flawlessly under Linux.

This snippet comes from compiling ddd under cygwin.
Similar problems have been reported. See:
http://www.cygwin.com/ml/cygwin/2003-11/msg01066.html

This is a dup of bug 9941.

*** This bug has been marked as a duplicate of 9941 ***