Subject: bug#14606: 24.2; semantics of `backward-delete-char' changed in 24, breaking programs

From: Taylor R Campbell <[email-masked]>
Date: Thu, 13 Jun 2013 15:26:33 +0000

This bug report will be sent to the Bug-GNU-Emacs mailing list
and the GNU bug tracker at debbugs.gnu.org.  Please check that
the From: line contains a valid email address.  After a delay of up
to one day, you should receive an acknowledgement at that address.

Please write in English if possible, as the Emacs maintainers
usually do not have translators for other languages.

Please describe exactly what actions triggered the bug, and
the precise symptoms of the bug.  If you can, give a recipe
starting from `emacs -Q':

In GNU Emacs 24, the semantics of `backward-delete-char' changed so
that it sometimes does far, far more than just deleting a character
backward.  This needlessly breaks programs that assumed it would do
just that, such as paredit.  In particular, if the region is active
and transient mark mode is enabled, it deletes the region, which, in
the case of paredit, wreaks havoc with the buffer.  If you want to
change the semantics, change the name, just like with
`backward-delete-char-untabify'.

If Emacs crashed, and you have the Emacs process in the gdb debugger,
please include the output from the following gdb commands:
    `bt full' and `xbacktrace'.
For information about debugging Emacs, please read the file
/pkg/current/pkg/share/emacs/24.2/etc/DEBUG.

In GNU Emacs 24.2.1 (x86_64--netbsd, X toolkit, Xaw scroll bars)
 of 2013-01-20 on manticore
Configured using:
 `configure
 '--srcdir=/tmp/pkg/current/work/editors/emacs24/work/emacs-24.2'
 '--localstatedir=/pkg/current/pkg/var' '--without-dbus'
 '--x-includes=/usr/X11R7/include' '--x-libraries=/usr/X11R7/lib'
 '--with-x' '--with-xpm' '--with-jpeg' '--with-tiff' '--with-gif'
 '--with-png' '--with-x-toolkit=athena' '--prefix=/pkg/current/pkg'
 '--build=x86_64--netbsd' '--host=x86_64--netbsd'
 '--infodir=/pkg/current/pkg/info' '--mandir=/pkg/current/pkg/man'
 'build_alias=x86_64--netbsd' 'host_alias=x86_64--netbsd' 'CC=cc'
 'CFLAGS=-I/pkg/current/pkg/include -I/usr/include -I/usr/X11R7/include
 -I/usr/X11R7/include/freetype2' 'LDFLAGS=-L/pkg/current/pkg/lib
 -L/usr/lib -Wl,-R/usr/lib -Wl,-R/pkg/current/pkg/lib -L/usr/X11R7/lib
 -Wl,-R/usr/X11R7/lib' 'LIBS=' 'CPPFLAGS=-DTERMINFO
 -I/pkg/current/pkg/include -I/usr/include -I/usr/X11R7/include
 -I/usr/X11R7/include/freetype2''

Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: C
  value of $LC_CTYPE: nil
  value of $LC_MESSAGES: nil
  value of $LC_MONETARY: nil
  value of $LC_NUMERIC: nil
  value of $LC_TIME: nil
  value of $LANG: en_US.UTF-8
  value of $XMODIFIERS: nil
  locale-coding-system: utf-8-unix
  default enable-multibyte-characters: t

Major mode: Fundamental

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

Recent input:
ESC x r e p o r t SPC e m a c s SPC b u g SPC DEL 
RET

Recent messages:
("emacs")
Loading term/xterm...done
For information about GNU Emacs and the GNU system, type C-h C-a.

Load-path shadows:
None found.

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