From: Eli Zaretskii <eliz@gnu.org>
To: Andrea Corallo <acorallo@gnu.org>
Cc: monnier@iro.umontreal.ca, emacs-devel@gnu.org,
stefankangas@gmail.com, adam@alphapapa.net,
arthur.miller@live.com
Subject: Re: Declaring Lisp function types
Date: Thu, 02 May 2024 14:15:28 +0300 [thread overview]
Message-ID: <86le4slb1r.fsf@gnu.org> (raw)
In-Reply-To: <yp1y18s4j51.fsf@fencepost.gnu.org> (message from Andrea Corallo on Thu, 02 May 2024 06:12:42 -0400)
> From: Andrea Corallo <acorallo@gnu.org>
> Cc: monnier@iro.umontreal.ca, emacs-devel@gnu.org, stefankangas@gmail.com,
> adam@alphapapa.net, arthur.miller@live.com
> Date: Thu, 02 May 2024 06:12:42 -0400
>
> Eli Zaretskii <eliz@gnu.org> writes:
>
> > The text you added says an incorrect type produces undefined behavior.
> > Is that true for all alternatives of calling the function:
> > interpreted, byte-compiled, and native-compiled, or only with some of
> > these?
>
> AFAIK only native-compiled ATM. Do you think we should specify that?
Yes, please.
> > "Undefined behavior" sounds scary, and I wonder whether it is really
> > accurate. If the practical expressions of this UB are only some
> > specific ones, perhaps we should mention them? For example, UB
> > generally means your entire system could be brought down, but I very
> > much doubt that this could happen due to incorrect type declaration,
> > could it?
>
> There are probably very few cases that can cause this (ATM I could think
> only of one) but if one pokes at that is actually not that difficult:
>
> (defun foo ()
> (declare (type (function () cons)))
> 3)
>
> (defun bar ()
> (car (foo)))
>
> Compiling this code and calling car crashes my Emacs.
It would be fine for now to say that incorrect type declaration could
crash Emacs if the code is natively-compiled and loaded.
next prev parent reply other threads:[~2024-05-02 11:15 UTC|newest]
Thread overview: 72+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-02-23 16:02 Declaring Lisp function types Andrea Corallo
2024-02-23 23:35 ` Adam Porter
2024-02-24 7:10 ` Eli Zaretskii
2024-02-24 8:53 ` Tomas Hlavaty
2024-02-24 9:08 ` Adam Porter
2024-02-24 9:24 ` Andrea Corallo
2024-02-24 15:13 ` Tomas Hlavaty
2024-02-24 15:21 ` Tomas Hlavaty
2024-02-24 15:24 ` Tomas Hlavaty
2024-02-24 8:56 ` Adam Porter
2024-02-24 10:03 ` Eli Zaretskii
2024-02-25 7:35 ` Adam Porter
2024-02-24 9:21 ` Andrea Corallo
2024-02-25 17:04 ` Alan Mackenzie
2024-02-25 17:15 ` Eli Zaretskii
2024-02-25 17:16 ` [External] : " Drew Adams
2024-02-26 16:25 ` Andrea Corallo
2024-02-29 3:50 ` Richard Stallman
2024-02-29 6:10 ` Adam Porter
2024-02-29 9:02 ` Andrea Corallo
2024-02-26 3:38 ` Richard Stallman
2024-02-26 16:38 ` [External] : " Drew Adams
2024-02-26 16:54 ` Eli Zaretskii
2024-02-26 17:44 ` Andrea Corallo
2024-02-26 16:52 ` Andrea Corallo
2024-02-26 18:10 ` Tomas Hlavaty
2024-03-02 21:19 ` Stefan Monnier via Emacs development discussions.
2024-03-03 9:52 ` Andrea Corallo
2024-03-03 14:52 ` Stefan Monnier
2024-03-03 17:31 ` Andrea Corallo
2024-03-03 18:13 ` Stefan Monnier
2024-03-15 16:49 ` Andrea Corallo
2024-03-15 18:19 ` Tomas Hlavaty
2024-03-15 18:38 ` Eli Zaretskii
2024-03-16 13:39 ` Tomas Hlavaty
2024-03-16 14:06 ` Eli Zaretskii
2024-03-16 14:56 ` Tomas Hlavaty
2024-03-16 15:43 ` Emanuel Berg
2024-03-16 15:44 ` Eli Zaretskii
2024-03-16 15:54 ` Emanuel Berg
2024-03-18 8:55 ` Lele Gaifax
2024-03-16 0:01 ` Adam Porter
2024-03-18 9:25 ` Andrea Corallo
2024-03-26 10:13 ` Andrea Corallo
2024-03-26 10:28 ` Christopher Dimech
2024-03-26 12:55 ` Eli Zaretskii
2024-03-26 16:46 ` Andrea Corallo
2024-04-29 17:48 ` Andrea Corallo
2024-04-29 17:55 ` Stefan Monnier
2024-04-29 18:42 ` Andrea Corallo
2024-04-30 14:55 ` Eli Zaretskii
2024-04-30 18:29 ` Stefan Monnier
2024-05-01 20:57 ` Andrea Corallo
2024-05-01 21:06 ` Stefan Monnier
2024-05-02 6:16 ` Eli Zaretskii
2024-05-02 10:16 ` Andrea Corallo
2024-05-02 6:15 ` Eli Zaretskii
2024-05-02 10:12 ` Andrea Corallo
2024-05-02 11:15 ` Eli Zaretskii [this message]
2024-05-02 13:20 ` Stefan Monnier
2024-05-01 20:54 ` Andrea Corallo
2024-05-02 10:22 ` Eli Zaretskii
2024-05-02 15:18 ` Andrea Corallo
2024-05-02 16:32 ` Eli Zaretskii
2024-03-26 13:05 ` Mattias Engdegård
2024-03-26 13:44 ` Stefan Monnier
2024-03-26 14:28 ` Joost Kremers
2024-03-26 14:37 ` Stefan Monnier
-- strict thread matches above, loose matches on Subject: below --
2024-03-16 7:46 Arthur Miller
2024-03-16 15:46 ` Emanuel Berg
2024-03-18 9:02 ` Andrea Corallo
2024-03-18 9:58 ` Arthur Miller
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