Don't cons with #'mapcar calls where the result is discarded, decide on mapc-internal at compile time if the Common Lisp functionality is not being used. 2009-10-12 Aidan Kehoe <kehoea@parhasard.net> * cl-macs.el (mapc): New compiler macro, use mapc-internal at compile time if we're not using the Common Lisp functionality. * bytecomp.el (byte-compile-mapcar, byte-compile-maplist): New. If the return value of mapcar is being discarded, compile it to a mapc-internal call instead, and warn, because the programmer probably can't rely on always being compiled by an XEmacs that does this. Similarly for maplist and mapl; and use byte-compile-funarg for map, mapl, mapcan, mapcon.

*** X11.def.old	Thu Apr 10 07:29:27 1997
--- X11.def	Wed Jul 02 22:20:16 1997
***************
*** 5,15 ****
  VERSION 6.1
  EXPORTS
   _Xdebug_p=_Xdebug CONSTANT
-  _XCreateMutex_fn_p=_XCreateMutex_fn CONSTANT
-  _XFreeMutex_fn_p=_XFreeMutex_fn CONSTANT
-  _XLockMutex_fn_p=_XLockMutex_fn CONSTANT
-  _XUnlockMutex_fn_p=_XUnlockMutex_fn CONSTANT
-  _Xglobal_lock_p=_Xglobal_lock CONSTANT
   XActivateScreenSaver
   XAddConnectionWatch
   XAddExtension
--- 5,10 ----
***************
*** 623,630 ****
   _XUnregisterFilter
   _XUnregisterInternalConnection
   _XVIDtoVisual
-  _Xthread_init
-  _Xthread_waiter
   XkbIgnoreExtension
   XkbOpenDisplay
   XkbQueryExtension
--- 618,623 ----