* bug#25088: 25.1; feature-unload and reload of cl-defstruct fails
@ 2016-12-02 5:24 npostavs
2016-12-02 8:13 ` Eli Zaretskii
0 siblings, 1 reply; 11+ messages in thread
From: npostavs @ 2016-12-02 5:24 UTC (permalink / raw)
To: 25088
[-- Attachment #1: Type: text/plain, Size: 981 bytes --]
tags: patch
Running
emacs -Q -l bug-struct-reload.el --eval "(unload-feature 'bug-struct-reload)" -l bug-struct-reload.el
Where bug-struct-reload.el contains
(eval-when-compile (require 'cl-lib))
(cl-defstruct foo f1)
(provide 'bug-struct-reload)
Shows in *Messages* the following error
Unexpected element (define-type . foo) in load-history
Compiler-macro error for foo-p: (void-function foo-p--cmacro) [2 times]
This is because cl-defstruct defines the field accessors before the
predicate. After calling `feature-unload', the `macro-compiler' symbol
property remains on the predicate even though the function itself is
undefined. Then when reloading, the compiler tries to call the
predicate's compiler-macro to inline it in the accessor function, and
fails to find the definition.
Since this is a regression in 25.1, I'd like to apply the following
patch to emacs-25, which simply puts the predicate definition before the
accessor functions.
[-- Attachment #2: patch --]
[-- Type: text/plain, Size: 2027 bytes --]
From d6285c44150fc9f6d0d3d6dadcd272bae3c498e5 Mon Sep 17 00:00:00 2001
From: Noam Postavsky <npostavs@gmail.com>
Date: Fri, 2 Dec 2016 00:03:57 -0500
Subject: [PATCH v1] Define struct predicate before acccesors
The accessor functions use the predicate function, which causes problems
when reloading after unload-feature: the compiler-macro property is
still present on the predicate symbol, and the compiler fails to find
the definition when trying to inline it into the accessor function.
* lisp/emacs-lisp/cl-macs.el (cl-defstruct): Move predicate definition
before field accessor definitions.
---
lisp/emacs-lisp/cl-macs.el | 16 ++++++++--------
1 file changed, 8 insertions(+), 8 deletions(-)
diff --git a/lisp/emacs-lisp/cl-macs.el b/lisp/emacs-lisp/cl-macs.el
index c51ed9d..b3a60b1 100644
--- a/lisp/emacs-lisp/cl-macs.el
+++ b/lisp/emacs-lisp/cl-macs.el
@@ -2687,6 +2687,14 @@ cl-defstruct
(= safety 1))
(cons 'and (cl-cdddr pred-form))
`(,predicate cl-x))))
+ (when pred-form
+ (push `(cl-defsubst ,predicate (cl-x)
+ (declare (side-effect-free error-free))
+ ,(if (eq (car pred-form) 'and)
+ (append pred-form '(t))
+ `(and ,pred-form t)))
+ forms)
+ (push `(put ',name 'cl-deftype-satisfies ',predicate) forms))
(let ((pos 0) (descp descs))
(while descp
(let* ((desc (pop descp))
@@ -2741,14 +2749,6 @@ cl-defstruct
(setq pos (1+ pos))))
(setq slots (nreverse slots)
defaults (nreverse defaults))
- (when pred-form
- (push `(cl-defsubst ,predicate (cl-x)
- (declare (side-effect-free error-free))
- ,(if (eq (car pred-form) 'and)
- (append pred-form '(t))
- `(and ,pred-form t)))
- forms)
- (push `(put ',name 'cl-deftype-satisfies ',predicate) forms))
(and copier
(push `(defalias ',copier #'copy-sequence) forms))
(if constructor
--
2.9.3
^ permalink raw reply related [flat|nested] 11+ messages in thread* bug#25088: 25.1; feature-unload and reload of cl-defstruct fails
2016-12-02 5:24 bug#25088: 25.1; feature-unload and reload of cl-defstruct fails npostavs
@ 2016-12-02 8:13 ` Eli Zaretskii
2016-12-03 22:38 ` npostavs
0 siblings, 1 reply; 11+ messages in thread
From: Eli Zaretskii @ 2016-12-02 8:13 UTC (permalink / raw)
To: npostavs; +Cc: 25088
> From: npostavs@users.sourceforge.net
> Date: Fri, 02 Dec 2016 00:24:04 -0500
>
> Running
>
> emacs -Q -l bug-struct-reload.el --eval "(unload-feature 'bug-struct-reload)" -l bug-struct-reload.el
>
> Where bug-struct-reload.el contains
>
> (eval-when-compile (require 'cl-lib))
> (cl-defstruct foo f1)
> (provide 'bug-struct-reload)
>
> Shows in *Messages* the following error
>
> Unexpected element (define-type . foo) in load-history
> Compiler-macro error for foo-p: (void-function foo-p--cmacro) [2 times]
>
> This is because cl-defstruct defines the field accessors before the
> predicate. After calling `feature-unload', the `macro-compiler' symbol
> property remains on the predicate even though the function itself is
> undefined. Then when reloading, the compiler tries to call the
> predicate's compiler-macro to inline it in the accessor function, and
> fails to find the definition.
>
> Since this is a regression in 25.1, I'd like to apply the following
> patch to emacs-25, which simply puts the predicate definition before the
> accessor functions.
How risky is this change? cl-defstruct is a very widely used macro,
whereas unload-feature is a relatively obscure feature. Is it really
worth fixing the (IMO minor) error and risking to break Emacs 25.2?
I don't have an intuition I can trust in these matters, so I need you
and others who do to offer their opinions, after carefully considering
the pros and cons.
Thanks.
^ permalink raw reply [flat|nested] 11+ messages in thread
* bug#25088: 25.1; feature-unload and reload of cl-defstruct fails
2016-12-02 8:13 ` Eli Zaretskii
@ 2016-12-03 22:38 ` npostavs
2016-12-04 3:35 ` Eli Zaretskii
2016-12-09 16:27 ` Stefan Monnier
0 siblings, 2 replies; 11+ messages in thread
From: npostavs @ 2016-12-03 22:38 UTC (permalink / raw)
To: Eli Zaretskii; +Cc: 25088
Eli Zaretskii <eliz@gnu.org> writes:
>
> How risky is this change? cl-defstruct is a very widely used macro,
> whereas unload-feature is a relatively obscure feature. Is it really
> worth fixing the (IMO minor) error and risking to break Emacs 25.2?
>
> I don't have an intuition I can trust in these matters, so I need you
> and others who do to offer their opinions, after carefully considering
> the pros and cons.
I think it's safe, but I've been wrong before. I agree that
unload-feature is sufficiently obscure that this can go to master
instead of emacs-25.
Perhaps the real bug is that unload-feature doesn't undo `put', thus the
compiler-macro still hangs around.
^ permalink raw reply [flat|nested] 11+ messages in thread
* bug#25088: 25.1; feature-unload and reload of cl-defstruct fails
2016-12-03 22:38 ` npostavs
@ 2016-12-04 3:35 ` Eli Zaretskii
2016-12-09 5:08 ` npostavs
2016-12-09 16:27 ` Stefan Monnier
1 sibling, 1 reply; 11+ messages in thread
From: Eli Zaretskii @ 2016-12-04 3:35 UTC (permalink / raw)
To: npostavs; +Cc: 25088
> From: npostavs@users.sourceforge.net
> Cc: 25088@debbugs.gnu.org
> Date: Sat, 03 Dec 2016 17:38:36 -0500
>
> Eli Zaretskii <eliz@gnu.org> writes:
> >
> > How risky is this change? cl-defstruct is a very widely used macro,
> > whereas unload-feature is a relatively obscure feature. Is it really
> > worth fixing the (IMO minor) error and risking to break Emacs 25.2?
> >
> > I don't have an intuition I can trust in these matters, so I need you
> > and others who do to offer their opinions, after carefully considering
> > the pros and cons.
>
> I think it's safe, but I've been wrong before. I agree that
> unload-feature is sufficiently obscure that this can go to master
> instead of emacs-25.
Thanks. Any other opinions?
I will leave it for a few days for others to chime in.
> Perhaps the real bug is that unload-feature doesn't undo `put', thus the
> compiler-macro still hangs around.
If this means there could be another, safer way of fixing this, please
show the details.
^ permalink raw reply [flat|nested] 11+ messages in thread
* bug#25088: 25.1; feature-unload and reload of cl-defstruct fails
2016-12-04 3:35 ` Eli Zaretskii
@ 2016-12-09 5:08 ` npostavs
2016-12-09 8:22 ` Eli Zaretskii
0 siblings, 1 reply; 11+ messages in thread
From: npostavs @ 2016-12-09 5:08 UTC (permalink / raw)
To: Eli Zaretskii; +Cc: 25088
Eli Zaretskii <eliz@gnu.org> writes:
>> Perhaps the real bug is that unload-feature doesn't undo `put', thus the
>> compiler-macro still hangs around.
>
> If this means there could be another, safer way of fixing this, please
> show the details.
Not sure how much safer this is, I think we would have to record the
which symbol plists are being modified during `load' so that
`unload-feature' could find them in `load-history' and reverse them
along with functions definitions. This would get rid of the
compiler-macro entries that were added to cl-defstruct accessor function
symbols, and so they would load successfully the second time round just
like the first (presumably).
^ permalink raw reply [flat|nested] 11+ messages in thread
* bug#25088: 25.1; feature-unload and reload of cl-defstruct fails
2016-12-09 5:08 ` npostavs
@ 2016-12-09 8:22 ` Eli Zaretskii
2016-12-09 23:33 ` Dmitry Gutov
0 siblings, 1 reply; 11+ messages in thread
From: Eli Zaretskii @ 2016-12-09 8:22 UTC (permalink / raw)
To: npostavs, Stefan Monnier, Dmitry Gutov; +Cc: 25088
> From: npostavs@users.sourceforge.net
> Cc: 25088@debbugs.gnu.org
> Date: Fri, 09 Dec 2016 00:08:28 -0500
>
> > If this means there could be another, safer way of fixing this, please
> > show the details.
>
> Not sure how much safer this is, I think we would have to record the
> which symbol plists are being modified during `load' so that
> `unload-feature' could find them in `load-history' and reverse them
> along with functions definitions. This would get rid of the
> compiler-macro entries that were added to cl-defstruct accessor function
> symbols, and so they would load successfully the second time round just
> like the first (presumably).
It could be safer because it doesn't change cl-defstruct. But it's
hard to tell without seeing an implementation.
What do others think? Is the patch proposed by Noam safe enough for
the release branch? Stefan? Dmitry?
Thanks.
^ permalink raw reply [flat|nested] 11+ messages in thread
* bug#25088: 25.1; feature-unload and reload of cl-defstruct fails
2016-12-09 8:22 ` Eli Zaretskii
@ 2016-12-09 23:33 ` Dmitry Gutov
2016-12-10 7:18 ` Eli Zaretskii
0 siblings, 1 reply; 11+ messages in thread
From: Dmitry Gutov @ 2016-12-09 23:33 UTC (permalink / raw)
To: Eli Zaretskii, npostavs, Stefan Monnier; +Cc: 25088
On 09.12.2016 10:22, Eli Zaretskii wrote:
> What do others think? Is the patch proposed by Noam safe enough for
> the release branch? Stefan? Dmitry?
Personally, the first option sounds safer for me (for the release
branch), because the other one might affect many packages and not just
this one.
^ permalink raw reply [flat|nested] 11+ messages in thread
* bug#25088: 25.1; feature-unload and reload of cl-defstruct fails
2016-12-09 23:33 ` Dmitry Gutov
@ 2016-12-10 7:18 ` Eli Zaretskii
2016-12-10 9:49 ` Dmitry Gutov
2016-12-10 21:05 ` npostavs
0 siblings, 2 replies; 11+ messages in thread
From: Eli Zaretskii @ 2016-12-10 7:18 UTC (permalink / raw)
To: Dmitry Gutov; +Cc: monnier, 25088, npostavs
> Cc: 25088@debbugs.gnu.org
> From: Dmitry Gutov <dgutov@yandex.ru>
> Date: Sat, 10 Dec 2016 01:33:57 +0200
>
> On 09.12.2016 10:22, Eli Zaretskii wrote:
>
> > What do others think? Is the patch proposed by Noam safe enough for
> > the release branch? Stefan? Dmitry?
>
> Personally, the first option sounds safer for me (for the release
> branch), because the other one might affect many packages and not just
> this one.
By "first option" do you mean the original patch posted by Noam?
If so, given a similar opinion from Stefan, let's install that on
emacs-25.
^ permalink raw reply [flat|nested] 11+ messages in thread
* bug#25088: 25.1; feature-unload and reload of cl-defstruct fails
2016-12-10 7:18 ` Eli Zaretskii
@ 2016-12-10 9:49 ` Dmitry Gutov
2016-12-10 21:05 ` npostavs
1 sibling, 0 replies; 11+ messages in thread
From: Dmitry Gutov @ 2016-12-10 9:49 UTC (permalink / raw)
To: Eli Zaretskii; +Cc: monnier, 25088, npostavs
On 10.12.2016 09:18, Eli Zaretskii wrote:
> By "first option" do you mean the original patch posted by Noam?
Yup!
^ permalink raw reply [flat|nested] 11+ messages in thread
* bug#25088: 25.1; feature-unload and reload of cl-defstruct fails
2016-12-10 7:18 ` Eli Zaretskii
2016-12-10 9:49 ` Dmitry Gutov
@ 2016-12-10 21:05 ` npostavs
1 sibling, 0 replies; 11+ messages in thread
From: npostavs @ 2016-12-10 21:05 UTC (permalink / raw)
To: Eli Zaretskii; +Cc: monnier, 25088, Dmitry Gutov
tags 25088 fixed
close 25088 25.2
quit
Eli Zaretskii <eliz@gnu.org> writes:
>> Cc: 25088@debbugs.gnu.org
>> From: Dmitry Gutov <dgutov@yandex.ru>
>> Date: Sat, 10 Dec 2016 01:33:57 +0200
>>
>> On 09.12.2016 10:22, Eli Zaretskii wrote:
>>
>> > What do others think? Is the patch proposed by Noam safe enough for
>> > the release branch? Stefan? Dmitry?
>>
>> Personally, the first option sounds safer for me (for the release
>> branch), because the other one might affect many packages and not just
>> this one.
>
> By "first option" do you mean the original patch posted by Noam?
>
> If so, given a similar opinion from Stefan, let's install that on
> emacs-25.
Okay, pushed as e4ac4507968b.
^ permalink raw reply [flat|nested] 11+ messages in thread
* bug#25088: 25.1; feature-unload and reload of cl-defstruct fails
2016-12-03 22:38 ` npostavs
2016-12-04 3:35 ` Eli Zaretskii
@ 2016-12-09 16:27 ` Stefan Monnier
1 sibling, 0 replies; 11+ messages in thread
From: Stefan Monnier @ 2016-12-09 16:27 UTC (permalink / raw)
To: npostavs; +Cc: 25088
> I think it's safe, but I've been wrong before.
I also think it's safe, and I've also been wrong before.
Another thing: the patch makes sense regardless of the change, since
it's good to define the things before we use them.
> Not sure how much safer this is, I think we would have to record the
> which symbol plists are being modified during `load' so that
> `unload-feature' could find them in `load-history' and reverse them
> along with functions definitions. This would get rid of the
> compiler-macro entries that were added to cl-defstruct accessor function
> symbols, and so they would load successfully the second time round just
> like the first (presumably).
Yes, that would be good. Currently unload-feature automatically un-does
defalias and defvar, more or less, but it would be good to extend this
to other top-level operations like `put`.
Stefan
^ permalink raw reply [flat|nested] 11+ messages in thread
end of thread, other threads:[~2016-12-10 21:05 UTC | newest]
Thread overview: 11+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2016-12-02 5:24 bug#25088: 25.1; feature-unload and reload of cl-defstruct fails npostavs
2016-12-02 8:13 ` Eli Zaretskii
2016-12-03 22:38 ` npostavs
2016-12-04 3:35 ` Eli Zaretskii
2016-12-09 5:08 ` npostavs
2016-12-09 8:22 ` Eli Zaretskii
2016-12-09 23:33 ` Dmitry Gutov
2016-12-10 7:18 ` Eli Zaretskii
2016-12-10 9:49 ` Dmitry Gutov
2016-12-10 21:05 ` npostavs
2016-12-09 16:27 ` Stefan Monnier
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