bug#3647: 23.1.50; defun* generates incorrect code for handling arglist keyword lookup

[Miles Bader]

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


Given the following code:

   (require 'cl)
   (defun* oink (&key a b) (list a b))

then evaluating:

   (oink :b :a :a 42)
   => (:a :a)

... which is incorrect.  The correct answer is (42 :A).

Looking at the macro-expansion of the above defun* form, the reason is
obvious:  the generated code uses (car (cdr (memq KEYWORD ARGLIST))) to
look up keyword argument values, which is obviously bogus if a preceding
argument value is the same as a keyword.  It would be more correct to
use (plist-get ARGUMENT KEYWORD), and that's what common-lisp systems I
tested return for this test.

However, the code in cl.el that generates keyword handling code is so
confusing, I'm not really sure how to fix this; presumably something in
`cl-do-arglist'?

Thanks,

-Miles


If Emacs crashed, and you have the Emacs process in the gdb debugger,
please include the output from the following gdb commands:
    `bt full' and `xbacktrace'.
If you would like to further debug the crash, please read the file
/usr/local/share/emacs/23.1.50/etc/DEBUG for instructions.


In GNU Emacs 23.1.50.1 (x86_64-unknown-linux-gnu, GTK+ Version 2.16.2)
 of 2009-06-22 on dhlpc061
Windowing system distributor `The X.Org Foundation', version 11.0.10601901
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  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: ja_JP.UTF-8
  value of $XMODIFIERS: @im=SCIM
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