writeln() assertion failed in hybrid x64

[Szymon Gatner via Digitalmars-d-learn]

Hey,

I am trying to build hybrid (C++, D) application (more here: 
http://forum.dlang.org/thread/ugkpqprobonorbdunxsx@forum.dlang.org) 
but I am now getting assertion failure from within writeln(). 
writeln() is called from a D function that has C++ linkage:

D definition:

extern (C++) void printSomething()
{
   writeln("hello from D");
}


usage from C++:

extern "C++" void printSomething();

int main()
{
   DRuntime druntime; // rt_init(), rt_term()
   printSomething();
}

this causes run-time assertion in fprintf() called from within 
writeln():

int __cdecl fprintf (
         FILE *str,
         const char *format,
         ...
         )
/*
  * 'F'ile (stream) 'PRINT', 'F'ormatted
  */
{
     va_list(arglist);
     FILE *stream;
     int buffing;
     int retval=0;

     _VALIDATE_RETURN( (str != NULL), EINVAL, -1); <=== assetion 
here

[...]
}

meaning that str arg passed is null. writelns()'s call site:

         enforce(fprintf(.stdout._p.handle, "%.*s\n",
                         cast(int) args[0].length, args[0].ptr) >= 
0);

so for some reason .stdout._p.handle is null.