* DevNotes: Add entry cgf-000017.

* _cygtls.cc (_cygtls::call2): Use new exit_thread function in place of
ExitThread.
* miscfuncs.cc (thread_wrapper): Ditto.
* thread.cc (pthread::exit): Ditto.
(pthread_mutex::unlock): Set tid to NULL rather than 0.
(pthread_spinlock::unlock): Ditto.
* pinfo.cc (commune_process): Actually call lock_process constructor.
* sigproc.cc (exit_thread): New function.
(wait_sig): Handle __SIGTHREADEXIT case.  Don't just block rather than
returning from this function.
* sigproc.h (__SIGTHREADEXIT): New enum.
(exit_thread): Declare.
* sync.cc (muto::release): Accept a tls command-line argument.
* sync.h (muto::release): Accept a tls command-line parameter.  Default to
&_my_tls.

winsup/cygwin/sigproc.h

@@ -25,7 +25,8 @@ enum
   __SIGHOLD	    = -(NSIG + 7),
   __SIGNOHOLD	    = -(NSIG + 8),
   __SIGEXIT	    = -(NSIG + 9),
-  __SIGSETPGRP	    = -(NSIG + 10)
+  __SIGSETPGRP	    = -(NSIG + 10),
+  __SIGTHREADEXIT   = -(NSIG + 11)
 };
 #endif
 
@@ -87,6 +88,7 @@ void __stdcall sigalloc ();
 
 int kill_pgrp (pid_t, siginfo_t&);
 int killsys (pid_t, int);
+void exit_thread (DWORD) __attribute__ ((regparm(1), noreturn));
 
 extern "C" void sigdelayed ();