Conditionalise the old-* functions and byte codes at compile time. src/ChangeLog addition: 2011-03-15 Aidan Kehoe <kehoea@parhasard.net> * config.h.in (SUPPORT_CONFOUNDING_FUNCTIONS): New #define, equivalent NEED_TO_HANDLE_21_4_CODE by default, describing whether this XEmacs should support the old-eq, old-equal and related functions and byte codes. * bytecode.c (UNUSED): Only interpret old-eq, old-equal, old-memq if SUPPORT_CONFOUNDING_FUNCTIONS is defined. * data.c: Move Fold_eq to fns.c with the rest of the Fold_* functions. * fns.c: * fns.c (Fmemq): * fns.c (memq_no_quit): * fns.c (assoc_no_quit): * fns.c (Frassq): * fns.c (Fequal): * fns.c (Fold_equal): * fns.c (syms_of_fns): Group old-eq, old-equal, old-memq etc together, surround them with #ifdef SUPPORT_CONFOUNDING_FUNCTIONS. lisp/ChangeLog addition: 2011-03-15 Aidan Kehoe <kehoea@parhasard.net> * bytecomp.el: Don't generate the old-eq, old-memq, old-equal bytecodes any more, but keep the information about them around for the sake of the disassembler. man/ChangeLog addition: 2011-03-15 Aidan Kehoe <kehoea@parhasard.net> * lispref/objects.texi (Character Type): * lispref/objects.texi (Equality Predicates): No longer document `old-eq', `old-equal', they haven't been used in years. tests/ChangeLog addition: 2011-03-17 Aidan Kehoe <kehoea@parhasard.net> * automated/lisp-tests.el: Only test the various old-* function if old-eq is bound and a subr.

--- a/src/data.c	Mon Mar 14 21:04:45 2011 +0000
+++ b/src/data.c	Thu Mar 17 20:13:00 2011 +0000
@@ -183,24 +183,6 @@
   return EQ_WITH_EBOLA_NOTICE (object1, object2) ? Qt : Qnil;
 }
 
-DEFUN ("old-eq", Fold_eq, 2, 2, 0, /*
-Return t if the two args are (in most cases) the same Lisp object.
-
-Special kludge: A character is considered `old-eq' to its equivalent integer
-even though they are not the same object and are in fact of different
-types.  This is ABSOLUTELY AND UTTERLY HORRENDOUS but is necessary to
-preserve byte-code compatibility with v19.  This kludge is known as the
-\"char-int confoundance disease\" and appears in a number of other
-functions with `old-foo' equivalents.
-
-Do not use this function!
-*/
-       (object1, object2))
-{
-  /* #### blasphemy */
-  return HACKEQ_UNSAFE (object1, object2) ? Qt : Qnil;
-}
-
 DEFUN ("null", Fnull, 1, 1, 0, /*
 Return t if OBJECT is nil.
 */
@@ -3568,7 +3550,6 @@
   DEFSUBR (Fdiv);
 #endif
   DEFSUBR (Feq);
-  DEFSUBR (Fold_eq);
   DEFSUBR (Fnull);
   Ffset (intern ("not"), intern ("null"));
   DEFSUBR (Flistp);