* dcrt0.cc (dll_crt0_1): Initialize mainthread stuff here before anything needs

it.
* sigproc.cc (sigproc_init): Move mainthread initialization out of here.
* sigproc.h (sigthread): Add init() method.
(sigframe): Don't try to initialize muto.
* sync.cc: Undef WaitForSingleObject to avoid recursion.

winsup/cygwin/dcrt0.cc

@@ -22,6 +22,8 @@ details. */
 HANDLE NO_COPY hMainProc = NULL;
 HANDLE NO_COPY hMainThread = NULL;
 
+sigthread NO_COPY mainthread;		// ID of the main thread
+
 static NO_COPY char dummy_user_data[sizeof (per_process)] = {0};
 per_process NO_COPY *user_data = (per_process *) &dummy_user_data;
 
@@ -624,6 +626,9 @@ dll_crt0_1 ()
      or attach to the shared data structure if it's already running. */
   shared_init ();
 
+  mainthread.init ("mainthread"); // For use in determining if signals
+				  //  should be blocked.
+
   if (mypid)
     set_myself (cygwin_shared->p[mypid]);