bug#24013: 25.0.95; Emacs 25.x uses up all memory and needs to be killed

[Achim Gratz]

In GNU Emacs 25.0.95.1 (x86_64-suse-linux-gnu, GTK+ Version 3.20.6)
 of 2016-07-17 built on Gertrud
Repository revision: 9356fe239281ca15e12a4e5e93d7d00c56df2626
Windowing system distributor 'The X.Org Foundation', version 11.0.11803000
System Description:     openSUSE Tumbleweed (20160710) (x86_64)

Configured using:
 'configure -with-x --with-sound --with-xpm --with-jpeg --with-tiff
 --with-gif --with-png --with-rsvg --with-dbus --without-gpm
 --with-x-toolkit=gtk3 --with-file-notification=inotify
 --x-includes=/usr/include --x-libraries=/usr/lib64 --with-xft
 --with-libotf --with-m17n-flt --with-pop --without-hesiod
 --with-kerberos --with-kerberos5 --with-xim --with-wide-int
 --enable-autodepend 'CFLAGS=-fomit-frame-pointer -fmessage-length=0
 -grecord-gcc-switches -fstack-protector -O2 -Wall -D_FORTIFY_SOURCE=2
 -funwind-tables -fasynchronous-unwind-tables -g -D_GNU_SOURCE
 -std=gnu99 -pipe -Wno-pointer-sign -Wno-unused-variable
 -Wno-unused-label -Wno-unprototyped-calls -fno-optimize-sibling-calls
 -DSYSTEM_PURESIZE_EXTRA=55000 -DSITELOAD_PURESIZE_EXTRA=10000 '
 'LDFLAGS=-Wl,-O2 -Wl,--hash-size=65521'
 
'--enable-locallisppath=${datadir}/emacs/${version}/site-lisp:${datadir}/emacs/site-lisp:/usr/share/emacs/site-lisp''

Configured features:
XPM JPEG TIFF GIF PNG RSVG IMAGEMAGICK SOUND DBUS GCONF GSETTINGS NOTIFY
ACL LIBSELINUX GNUTLS LIBXML2 FREETYPE M17N_FLT LIBOTF XFT ZLIB
TOOLKIT_SCROLL_BARS GTK3 X11

Important settings:
  value of $LC_MESSAGES: POSIX
  value of $LANG: de_DE.UTF-8
  value of $XMODIFIERS: @im=local
  locale-coding-system: utf-8-unix

Major mode: Text

Minor modes in effect:
  show-paren-mode: t
  tooltip-mode: t
  global-eldoc-mode: t
  electric-indent-mode: t
  mouse-wheel-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
  size-indication-mode: t
  column-number-mode: t
  line-number-mode: t
  transient-mark-mode: t


The file to reproduce this with contained sensitive information, but
fortunately the replacement of all information with something
inconspicous still produces the same crash (and makes it a lot smaller
after compression):

crash.txt.xz
Description: application/xz

It is a moderately large (~12500 lines, 585kiB) text
file with UNIX line endings (\n).  Mixed in with the normal text are
protocol logs that have \r\n line endings.  I have confirmed that
replacement of those line endings will stop the bug from happening.  The
bug happens with all 25.x versions I have including master, the earliest
one I can still test is from February 27th this year.

To reproduce, set a mark (C-Space) somewhere in the file.  Then
extend/shrink the selection region by doing Shift-PgUp / Shift-PgDwn,
going back and forth several times.  Once you've crossed a portion of
the file that has the "foreign" line endings, as soon as you take your
finger off the Shift key Emacs becomes unresponsive (the cursor
vanishes).  Several seconds later it starts allocating memory in an
apparently exponential fashion until it has exhausted both physical and
swap, while maxing out one CPU core.  The process must be killed.

Trying the same recipe with Emacs 24.5 yields a short phase of
unresponsiveness with the cursor vanished, then it returns with an error
message "Timed out waiting for property-notify event".

I consider this a blocker for the upcoming 25.1 release.


Regards,
Achim.
-- 
+<[Q+ Matrix-12 WAVE#46+305 Neuron microQkb Andromeda XTk Blofeld]>+

SD adaptations for Waldorf Q V3.00R3 and Q+ V3.54R2:
http://Synth.Stromeko.net/Downloads.html#WaldorfSDada