bug#23955: 24.5; Unexpected behavior of built-in function `transpose-regions'

bug#23955: 24.5; Unexpected behavior of built-in function `transpose-regions'

[Gustavo Tavares Cabral]

================ BEGINNING OF FILE ================
;; ((right))((left))
;; Expected result: ((left))((right))
;;  Current result: ((left)(((right))
;; Emacs version: 24.5
;; Command args: $ emacs -Q

(transpose-regions 6 11 15 19)  ;; should transpose "right" and "left"
================ END OF FILE ================



In GNU Emacs 24.5.1 (x86_64-unknown-linux-gnu, GTK+ Version 3.10.8)
 of 2016-01-04 on gustavo-VirtualBox
Windowing system distributor `The X.Org Foundation', version 11.0.11701000
System Description:	Ubuntu 14.04.3 LTS

Configured using:
 `configure --prefix=/home/gustavo/prefix'

Important settings:
  value of $LANG: pt_BR.UTF-8
  value of $XMODIFIERS: @im=ibus
  locale-coding-system: utf-8-unix

Major mode: Emacs-Lisp

Minor modes in effect:
  tooltip-mode: t
  electric-indent-mode: t
  mouse-wheel-mode: t
  tool-bar-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.
nil
Undo!
Beginning of buffer [3 times]
Mark set
End of buffer [2 times]
Making completion list... [2 times]

Load-path shadows:
None found.

Features:
(shadow sort gnus-util mail-extr emacsbug message format-spec rfc822 mml
mml-sec mm-decode mm-bodies mm-encode mail-parse rfc2231 mailabbrev
gmm-utils mailheader sendmail rfc2047 rfc2045 ietf-drums mm-util
help-fns mail-prsvr mail-utils help-mode easymenu time-date tooltip
electric uniquify ediff-hook vc-hooks lisp-float-type mwheel x-win x-dnd
tool-bar dnd fontset image regexp-opt fringe tabulated-list newcomment
lisp-mode prog-mode register page menu-bar rfn-eshadow timer select
scroll-bar mouse jit-lock font-lock syntax facemenu font-core frame cham
georgian utf-8-lang misc-lang vietnamese tibetan thai tai-viet lao
korean japanese hebrew greek romanian slovak czech european ethiopic
indian cyrillic chinese case-table epa-hook jka-cmpr-hook help simple
abbrev minibuffer nadvice loaddefs button faces cus-face macroexp files
text-properties overlay sha1 md5 base64 format env code-pages mule
custom widget hashtable-print-readable backquote make-network-process
dbusbind gfilenotify dynamic-setting system-font-setting
font-render-setting move-toolbar gtk x-toolkit x multi-tty emacs)

Memory information:
((conses 16 72640 9067)
 (symbols 48 17639 0)
 (miscs 40 44 188)
 (strings 32 9295 4624)
 (string-bytes 1 258944)
 (vectors 16 8991)
 (vector-slots 8 383829 17105)
 (floats 8 65 248)
 (intervals 56 213 24)
 (buffers 960 13)
 (heap 1024 43780 921))

bug#23955: 24.5; Unexpected behavior of built-in function `transpose-regions'

[Tino Calancha]

I cannot reproduce the bug:

emacs -Q
;; Evaluate following form
(let* ((str ";; ((right))((left))")
        (expected ";; ((left))((right))")
        (result (with-temp-buffer
                  (insert str)
                  (transpose-regions 6 11 15 19)
                  (buffer-string))))
   (string= result expected))
=> t

In GNU Emacs 24.5.1 (x86_64-pc-linux-gnu, GTK+ Version 3.18.9)
  of 2016-04-08 on binet, modified by Debian
Windowing system distributor `The X.Org Foundation', version 11.0.11803000
System Description:	Debian GNU/Linux testing (stretch)

bug#23955: 24.5; Unexpected behavior of built-in function `transpose-regions'

[Gustavo Tavares Cabral]

[-- Attachment #1: Type: text/plain, Size: 201 bytes --]

I've fixed the bug replacing a single `memcpy' with `memmove' (function
`Ftranspose_regions' in file `editfns.c'). The bug is already fixed for the
next version (bug #19213).

Thanks for the patience.

[-- Attachment #2: Type: text/html, Size: 264 bytes --]

Backport fix for Bug #19213/#23955

[npostavs]

This bug was fixed replacing a memcpy with a memmove, which is safe by
definition, so I think we should backport it to emacs-25.

354f9f0f "Use memmove instead of memcpy on overlapping regions"

http://debbugs.gnu.org/cgi/bugreport.cgi?bug=19213
http://debbugs.gnu.org/cgi/bugreport.cgi?bug=23955

Re: Backport fix for Bug #19213/#23955

[John Wiegley]

>>>>> "n" == npostavs  <npostavs@users.sourceforge.net> writes:

n> This bug was fixed replacing a memcpy with a memmove, which is safe by
n> definition, so I think we should backport it to emacs-25.

Looks safe to me.

-- 
John Wiegley                  GPG fingerprint = 4710 CF98 AF9B 327B B80F
http://newartisans.com                          60E1 46C4 BD1A 7AC1 4BA2

Re: Backport fix for Bug #19213/#23955

[Eli Zaretskii]

> From: John Wiegley <jwiegley@gmail.com>
> Date: Wed, 13 Jul 2016 17:33:11 -0700
> Cc: Gustavo Tavares Cabral <gustavotcabral@gmail.com>, emacs-devel@gnu.org
> 
> >>>>> "n" == npostavs  <npostavs@users.sourceforge.net> writes:
> 
> n> This bug was fixed replacing a memcpy with a memmove, which is safe by
> n> definition, so I think we should backport it to emacs-25.
> 
> Looks safe to me.

Agreed.

Re: Backport fix for Bug #19213/#23955

[Noam Postavsky]

unarchive 19213
fixed 19213 25.1
forcemerge 19213 23955
quit


On Thu, Jul 14, 2016 at 11:02 AM, Eli Zaretskii <eliz@gnu.org> wrote:
>> From: John Wiegley <jwiegley@gmail.com>
>> Date: Wed, 13 Jul 2016 17:33:11 -0700
>> Cc: Gustavo Tavares Cabral <gustavotcabral@gmail.com>, emacs-devel@gnu.org
>>
>> >>>>> "n" == npostavs  <npostavs@users.sourceforge.net> writes:
>>
>> n> This bug was fixed replacing a memcpy with a memmove, which is safe by
>> n> definition, so I think we should backport it to emacs-25.
>>
>> Looks safe to me.
>
> Agreed.

I've pushed to emacs-25 (916abe91fd).