bug#28293: 24.5; Haskell Mode Hangs on loading large complex file

[Mike Dupont <jamesmikedupont@googlemail.com>]

Load this large haskell file
it hangs emacs, I think it is something in the mode.

https://github.com/h4ck3rm1k3/gcc-ontology/blob/7889b822218950fcdc414a4e054d6e7bb4a3e52e/tests/test_haskell1_b.hs


In GNU Emacs 24.5.1 (x86_64-pc-linux-gnu, GTK+ Version 3.21.5)
 of 2016-09-05 on trouble, modified by Debian
System Description: Debian GNU/Linux unstable (sid)

Configured using:
 `configure --build x86_64-linux-gnu --prefix=/usr
 --sharedstatedir=/var/lib --libexecdir=/usr/lib
 --localstatedir=/var/lib --infodir=/usr/share/info
 --mandir=/usr/share/man --with-pop=yes
 --enable-locallisppath=/etc/emacs24:/etc/emacs:/usr/local/share/emacs/24.5/site-lisp:/usr/local/share/emacs/site-lisp:/usr/share/emacs/24.5/site-lisp:/usr/share/emacs/site-lisp
 --build x86_64-linux-gnu --prefix=/usr --sharedstatedir=/var/lib
 --libexecdir=/usr/lib --localstatedir=/var/lib
 --infodir=/usr/share/info --mandir=/usr/share/man --with-pop=yes
 --enable-locallisppath=/etc/emacs24:/etc/emacs:/usr/local/share/emacs/24.5/site-lisp:/usr/local/share/emacs/site-lisp:/usr/share/emacs/24.5/site-lisp:/usr/share/emacs/site-lisp
 --with-x=yes --with-x-toolkit=gtk3 --with-toolkit-scroll-bars
 'CFLAGS=-g -O2
 -fdebug-prefix-map=/build/emacs24-24.5+1=. -fstack-protector-strong
 -Wformat -Werror=format-security -Wall' 'CPPFLAGS=-Wdate-time
 -D_FORTIFY_SOURCE=2' LDFLAGS=-Wl,-z,relro'

Important settings:
  value of $LC_ALL: en_US.UTF-8
  value of $LANG: en_US.UTF-8
  locale-coding-system: utf-8-unix

Major mode: Haskell

Minor modes in effect:
  haskell-indentation-mode: t
  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
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent messages:
Loading /var/cache/dictionaries-common/emacsen-ispell-default.el (source)...done
Loading debian-ispell...done
Loading /var/cache/dictionaries-common/emacsen-ispell-dicts.el (source)...done
Loading /etc/emacs/site-start.d/50dictionaries-common.el (source)...done
Loading /etc/emacs/site-start.d/50python-docutils.el (source)...done
For information about GNU Emacs and the GNU system, type C-h C-a.
(New file)
Saving file /home/mdupont/experiments/gcc-ontology/tests/test.hs...
Wrote /home/mdupont/experiments/gcc-ontology/tests/test.hs
Making completion list...

Load-path shadows:
/usr/share/emacs/24.5/site-lisp/debian-startup hides
/usr/share/emacs/site-lisp/debian-startup
/usr/share/emacs24/site-lisp/cmake-data/cmake-mode hides
/usr/share/emacs/site-lisp/cmake-mode
/usr/share/emacs/site-lisp/rst hides /usr/share/emacs/24.5/lisp/textmodes/rst

Features:
(shadow sort 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 mail-utils help-mode
haskell haskell-completions haskell-load haskell-commands
highlight-uses-mode haskell-modules haskell-sandbox
haskell-navigate-imports haskell-repl haskell-collapse hideshow
haskell-debug haskell-interactive-mode haskell-presentation-mode
haskell-compile haskell-process haskell-session url-util haskell-hoogle
vc-git haskell-mode haskell-cabal haskell-utils haskell-font-lock
haskell-indentation haskell-string haskell-sort-imports haskell-lexeme
haskell-align-imports haskell-compat haskell-complete-module
haskell-ghc-support noutline outline easy-mmode flymake etags compile
comint ring dabbrev ansi-color haskell-customize xterm gh-common
gh-profile url-parse auth-source gnus-util time-date mm-util mail-prsvr
password-cache url-vars rx s marshal ht json dash eieio byte-opt
bytecomp byte-compile cl-extra cl-loaddefs cl-lib cconv eieio-core
advice help-fns info easymenu package epg-config 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 146806 6971)
 (symbols 48 25084 0)
 (miscs 40 75 131)
 (strings 32 33718 5931)
 (string-bytes 1 1113583)
 (vectors 16 15510)
 (vector-slots 8 444933 4851)
 (floats 8 80 365)
 (intervals 56 261 0)
 (buffers 960 14))


-- 
James Michael DuPont