XtManageChild broken???

[Ciccotelli Massimo <ciccotelli at cesi dot it>]

Hi all,
I have a port of a Linux application on Cygwin which worked fine using 
XFree version 4.1.0.

Executing the code after recompiling with version 4.2.0 it crashes 
(segmentation fault) when I try to open a menu.

I have tried to identify the problem (unfortunately I am not an X11 
expert); it seems due to a call of
XtManageChild !!!

Digging around in the Internet I have found a simple example which shows 
the same behaviour of my application. the code is the following:

#include <Xm/Xm.h>
#include <Xm/MainW.h>
#include <Xm/CascadeB.h>
#include <Xm/MessageB.h>
#include <Xm/PushB.h>

main(int argc, char *argv[])
{
   XtAppContext app;
   Widget top_wid, main_w, menu_bar, info, quit;


   /* callback for the pushbuttons.  pops up dialog */
   void info_pop_up(), quit_pop_up(); 
      
   top_wid = XtVaAppInitialize(&app, "Demos", NULL, 0,
       &argc, argv, NULL, NULL);

   main_w = XtVaCreateManagedWidget("main_window",
       xmMainWindowWidgetClass,   top_wid,
       XmNheight, 300,
       XmNwidth,300,
       NULL);

   menu_bar = XmCreateMenuBar(main_w, "main_list",
       NULL, 0);       
   XtManageChild(menu_bar);


   /* create quit widget + callback */
      
   quit = XtVaCreateManagedWidget( "Quit",
       xmCascadeButtonWidgetClass, menu_bar,
       XmNmnemonic, 'Q',
       NULL);
      
   /* Callback has data passed to */
  
   XtAddCallback(quit, XmNactivateCallback, quit_pop_up,
                  "Are you sure you want to quit?");

   XtRealizeWidget(top_wid);
   XtAppMainLoop(app);
}

void
quit_pop_up(Widget cascade_button, char *text,
XmPushButtonCallbackStruct *cbs)

{
   Widget dialog;
   XmString xm_string;
   void quit_activate();
   Arg args[1];

   /* label the dialog */
   xm_string = XmStringCreateSimple(text);
   XtSetArg(args[0], XmNmessageString, xm_string);


   /* Create the WarningDialog */
   dialog = XmCreateWarningDialog(cascade_button, "quit",
                                  args, 1);

   XmStringFree(xm_string);

   XtAddCallback(dialog, XmNokCallback, quit_activate,
                 NULL);

   XtManageChild(dialog);     // This call crashes the application.
   XtPopup(XtParent(dialog), XtGrabNone);
}


/* callback routines for dialogs */

void
quit_activate(Widget dialog)
{
   printf("Quit Ok was pressed.\n");
   exit(0);
}

This code compiles and run fine in my Linux (RH7.1) box.

Is it a bug???
Am I missing something??

I'm using cygwin 1.3.10 on Win98/Win NT 4 sp6

Thanks a lot,
Massimo