Re: COMPILE regression in Apr 2010 snapshot (?)

* Raymond Toy <[email protected]> :
Wrote on Sun, 25 Apr 2010 23:29:54 -0400:

| On 4/24/10 3:42 AM, Madhu wrote:
|> Helu, here is an unpolished test case to show the problem:
|>
|>   -=-=-
|> (defmacro frob-keyvals-string (string)
|>   (with-input-from-string (stream string)
|>     `(progn ,@(loop for key = (let ((x (read stream nil stream)))
|> 				(if (eq x stream) (loop-finish) x))
|> 		    for val = (read stream)
|> 		    for comment = (read stream)
|> 		    collect (list 'defvar key (list 'quote val)
|> 				  (string comment))))))
|>
|> (frob-keyvals-string "
|> foo fooval foocomment
|> bar barval barcomment
|> car carval carcomment")
|>   
| This is caused by the macro expansion of defvar when the localization
| support was added.  Previously, we had
|
| (macroexpand '(defvar abc nil "abc")) ->
| (PROGN
|   (DECLAIM (SPECIAL ABC))
|   (UNLESS (BOUNDP 'ABC)
|     (SETQ ABC NIL))
|   (SETF (DOCUMENTATION 'ABC 'VARIABLE) '"abc")
|   (LISP::SET-DEFVAR-SOURCE-LOCATION 'ABC (C::SOURCE-LOCATION))
|   'ABC)
|
| We now have:
|
| (PROGN
|   (DECLAIM (SPECIAL ABC))
|   (UNLESS (BOUNDP 'ABC)
|     (SETQ ABC NIL))
|   (SETF (DOCUMENTATION 'ABC 'VARIABLE) '"abc")
|   (EVAL-WHEN (:LOAD-TOPLEVEL :EXECUTE)
|     (SETF (INFO VARIABLE INTL:TEXTDOMAIN 'ABC) NIL))
|   (LISP::SET-DEFVAR-SOURCE-LOCATION 'ABC (C::SOURCE-LOCATION))
|   'ABC)
|
| I do not understand it, but that (setf info) causes the problem.  When
| that is removed, cmucl behaves as it used to.  I don't understand why
| that would cause the macro to be compiled again.


My report may have been misleading: I do not think that macro is being
compiled again, it just looks that way from the notes that CMUCL prints.

I have not looked at the CMUCL code yet, but I my guess (without looking
at any commits) is that this is more likely related to some source
recording changes that may have been introduced.

--
Madhu