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From: Stefan Monnier <monnier@iro.umontreal.ca>
To: Sean Whitton <spwhitton@spwhitton.name>
Cc: "xenodasein--- via Emacs development discussions."
	<emacs-devel@gnu.org>,
	 eliz@gnu.org,  xenodasein@tutanota.de
Subject: Re: Development Speed
Date: Fri, 24 Dec 2021 09:06:11 -0500	[thread overview]
Message-ID: <jwvo856je24.fsf-monnier+emacs@gnu.org> (raw)
In-Reply-To: <87czlm3hyf.fsf@melete.silentflame.com> (Sean Whitton's message of "Thu, 23 Dec 2021 18:33:12 -0700")

>> According to any of the C standards, Emacs is just one large undefined
>> behavior.
> Would you mind expanding on this remark briefly?  What sort of undefined
> behaviour do you have in mind?

Scanning the stack and playing with the lowest 3 bits of pointers come
to mind.  These are UB, and in C as soon as one UB is encountered during
execution, everything else from now on is potentially UB (more
specifically, the C standard allows the interpretation that a UB
operation does literally anything, including never terminating and
behaving eerily like your program).


        Stefan




  reply	other threads:[~2021-12-24 14:06 UTC|newest]

Thread overview: 100+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-12-22  0:52 Development Speed xenodasein--- via Emacs development discussions.
2021-12-22  1:16 ` Po Lu
2021-12-22 12:41 ` Eli Zaretskii
2021-12-22 15:15   ` xenodasein--- via Emacs development discussions.
2021-12-22 16:37     ` Eli Zaretskii
2021-12-23 13:36       ` xenodasein--- via Emacs development discussions.
2021-12-23 13:42         ` Po Lu
2021-12-23 13:48           ` xenodasein--- via Emacs development discussions.
2021-12-23 16:36             ` Stefan Monnier
2021-12-23 17:02               ` xenodasein--- via Emacs development discussions.
2021-12-24  0:21                 ` Po Lu
2021-12-24 20:21               ` Tim Cross
2021-12-23 16:35         ` Stefan Monnier
2021-12-23 17:35           ` xenodasein--- via Emacs development discussions.
2021-12-23 19:12             ` Stefan Monnier
2021-12-23 19:53               ` xenodasein--- via Emacs development discussions.
2021-12-23 20:10                 ` Stefan Monnier
2021-12-23 20:16                   ` Eli Zaretskii
2021-12-23 22:07                     ` xenodasein--- via Emacs development discussions.
2021-12-24  7:00                       ` Eli Zaretskii
2021-12-25  5:16               ` Richard Stallman
2021-12-25  5:22                 ` Po Lu
2021-12-25  7:03                 ` Eli Zaretskii
2021-12-25 15:55                 ` Stefan Monnier
2021-12-25  5:16             ` Richard Stallman
2021-12-24  1:33           ` Sean Whitton
2021-12-24 14:06             ` Stefan Monnier [this message]
2021-12-24 14:39               ` Óscar Fuentes
2021-12-22 15:21   ` xenodasein--- via Emacs development discussions.
2021-12-22 16:42     ` Eli Zaretskii
2021-12-23 13:57       ` xenodasein--- via Emacs development discussions.
2021-12-23 14:37         ` Eli Zaretskii
  -- strict thread matches above, loose matches on Subject: below --
2021-12-21 10:52 xenodasein--- via Emacs development discussions.
2021-12-21 11:05 ` Po Lu
2021-12-21 11:25   ` xenodasein--- via Emacs development discussions.
2021-12-21 11:37     ` Po Lu
2021-12-21 14:47       ` xenodasein--- via Emacs development discussions.
2021-12-22  0:56         ` Po Lu
2021-12-22  1:05           ` xenodasein--- via Emacs development discussions.
2021-12-21 12:05     ` Stefan Kangas
2021-12-21 12:20       ` Theodor Thornhill
2021-12-21 14:14       ` xenodasein--- via Emacs development discussions.
2021-12-21 14:48 ` Eli Zaretskii
2021-12-22  4:16 ` Richard Stallman
2021-12-22 10:09   ` Óscar Fuentes
2021-12-22 10:22     ` Po Lu
2021-12-22 10:38       ` Óscar Fuentes
2021-12-22 10:45         ` Po Lu
2021-12-22 13:47         ` Eli Zaretskii
2021-12-23  3:43         ` Richard Stallman
2021-12-23  9:50           ` Óscar Fuentes
2021-12-23 10:37             ` Po Lu
2021-12-23 10:52               ` Óscar Fuentes
2021-12-23 10:54               ` Arthur Miller
2021-12-24  4:13               ` Richard Stallman
2021-12-24  4:13             ` Richard Stallman
2021-12-22 14:21       ` Dmitry Gutov
2021-12-23  1:00         ` Po Lu
2021-12-23  1:05           ` Dmitry Gutov
2021-12-23  1:07             ` Po Lu
2021-12-23  2:18               ` dick
2021-12-23  6:39                 ` Eli Zaretskii
2021-12-23 10:46               ` Dmitry Gutov
2021-12-23 12:54                 ` Arthur Miller
2021-12-22 13:41     ` Eli Zaretskii
2021-12-22 15:51       ` Óscar Fuentes
2021-12-22 17:12         ` Eli Zaretskii
2021-12-22 18:49           ` Óscar Fuentes
2021-12-23  3:43     ` Richard Stallman
2021-12-23 10:13       ` Óscar Fuentes
2021-12-23 10:35         ` Po Lu
2021-12-23 10:47           ` Óscar Fuentes
2021-12-23 10:50             ` Po Lu
2021-12-23 10:59               ` Óscar Fuentes
2021-12-23 11:05                 ` Po Lu
2021-12-23 11:16                   ` Óscar Fuentes
2021-12-24  4:13           ` Richard Stallman
2021-12-24  4:13         ` Richard Stallman
2021-12-23 10:23       ` Arthur Miller
2021-12-24  4:13         ` Richard Stallman
2021-12-22 14:41   ` xenodasein--- via Emacs development discussions.
2021-12-19 17:06 xenodasein--- via Emacs development discussions.
2021-12-20  0:31 ` Po Lu
2021-12-20  4:16   ` xenodasein--- via Emacs development discussions.
2021-12-20  5:12     ` Po Lu
2021-12-20  8:16     ` Philip Kaludercic
2021-12-20 14:30     ` Stefan Monnier
2021-12-20 15:51       ` xenodasein--- via Emacs development discussions.
     [not found]     ` <MrLr14W--3-2@tutanota.de>
     [not found]       ` <87lf0f1vko.fsf@yahoo.com>
2021-12-20 15:49         ` xenodasein--- via Emacs development discussions.
2021-12-21  1:06           ` Po Lu
2021-12-21 10:25       ` xenodasein--- via Emacs development discussions.
2021-12-21 10:31         ` Po Lu
2021-12-21 14:39         ` Eli Zaretskii
2021-12-20 10:31 ` Lars Ingebrigtsen
2021-12-21  4:15 ` Richard Stallman
2021-12-21  5:55   ` Eli Zaretskii
2021-12-21 11:09   ` xenodasein--- via Emacs development discussions.
2021-12-21 14:52     ` Eli Zaretskii
2021-12-22  0:55       ` xenodasein--- via Emacs development discussions.
2021-12-22 12:44         ` Eli Zaretskii

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