[ clisp-Bugs-3451264 ] odd error with sort

[SourceForge.net <no...@so...>]

Bugs item #3451264, was opened at 2011-12-05 03:40
Message generated for change (Tracker Item Submitted) made by litwr
You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=101355&aid=3451264&group_id=1355

Please note that this message will contain a full copy of the comment thread,
including the initial issue submission, for this request,
not just the latest update.
Category: clisp
Group: lisp error
Status: Open
Resolution: None
Priority: 5
Private: No
Submitted By: Vladimir Lidovski (litwr)
Assigned to: Bruno Haible (haible)
Summary: odd error with sort

Initial Comment:
It is about GNU CLISP strange behaviours. The version 2.33/2.48/2.49 were tested. Can anybody explain this oddness?

(defun xsort (l) (sort l #'<)) ;XSORT
(setq l '(3 1 2)) ;(3 1 2)
(xsort l) ;(1 2 3)
l ; surprize! (1 2 3)

The ordinal lisp function XSORT takes its argument by value but the presence of SORT-function in its body converts argument to passed by reference! Are there any reasonable explanation? BTW the POP-function doesn't make surprize:

(defun xpop (l) (pop l)) ;XPOP
(setq l '(3 1 2)) ;(3 1 2)
(xpop l) ;3
l ;(3 2 1)


----------------------------------------------------------------------

You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=101355&aid=3451264&group_id=1355