setq failure following list manipulation

[Bill Lytton]

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In GNU Emacs 21.3.1 (x86_64-redhat-linux-gnu, X toolkit, Xaw3d scroll bars)
 of 2005-08-09 on dolly.build.redhat.com
configured using `configure  --host=x86_64-redhat-linux 
--build=x86_64-redhat-linux --target=x86_64-redhat-linux-gnu --program-prefix= 
--prefix=/usr --exec-prefix=/usr --bindir=/usr/bin --sbindir=/usr/sbin 
--sysconfdir=/etc --datadir=/usr/share --includedir=/usr/include 
--libdir=/usr/lib64 --libexecdir=/usr/libexec --localstatedir=/var 
--sharedstatedir=/usr/com --mandir=/usr/share/man --infodir=/usr/share/info 
--with-pop --with-sound'
Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: nil
  value of $LC_CTYPE: nil
  value of $LC_MESSAGES: nil
  value of $LC_MONETARY: nil
  value of $LC_NUMERIC: nil
  value of $LC_TIME: nil
  value of $LANG: en_US.UTF-8
  locale-coding-system: utf-8
  default-enable-multibyte-characters: t

Please describe exactly what actions triggered the bug
and the precise symptoms of the bug:

bug or feature?:

quoted arg for setq in function call no longer works after maninpulating list
using global variable

(defun ae ()  (setq nums '(1 2 3)))
(nconc nums (list 4))
(ae) ;; returns (1 2 3 4)
nums ;; returns (1 2 3 4)

Recent input:


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