* cygthread.h (cygthread::terminate): Declare new function.

(cygthread::initialized): Change to 'int'.
* cygthread.cc (cygthread::stub): Exit thread if initialized < 0.
(cygthread::new): Ditto.
(cygthread::runner): Ditto.  Set initialized using xor to preserve sign.
(cygthread::terminate): New function.
* dcrt0.cc (do_exit): Call cygthread::terminate.

winsup/cygwin/dcrt0.cc

@@ -1024,6 +1024,7 @@ do_exit (int status)
   window_terminate ();
   events_terminate ();
   shared_terminate ();
+  cygthread::terminate ();
 
   minimal_printf ("winpid %d, exit %d", GetCurrentProcessId (), n);
   myself->exit (n);