bug#8413: 23.3; follow-mode hides a line between visible parts of buffer

bug#8413: 23.3; follow-mode hides a line between visible parts of buffer

[Nicolas Goaziou]

When using follow-mode with frame splitted using `C-x 3', the last line
of the left-hand part of the buffer only appears partially, as if it was
hidden behind the mode-line. It is even more clear when calling
linum-mode, as a number is skipped between the two windows.

From `emacs -Q', C-h r, C-x 3, M-x follow-mode and there a line is
missing between the two parts of the buffer (Variable Index here).


In GNU Emacs 23.3.1 (x86_64-unknown-linux-gnu, GTK+ Version 2.22.1)
 of 2011-03-10 on bitzer.hoetzel.info
Windowing system distributor `The X.Org Foundation', version 11.0.10904901
configured using `configure  '--prefix=/usr' '--sysconfdir=/etc' '--libexecdir=/usr/lib' '--localstatedir=/var' '--mandir=/usr/share/man' '--without-sound' '--with-x-toolkit=gtk' 'CFLAGS=-march=x86-64 -mtune=generic -O2 -pipe -fno-optimize-sibling-calls' 'LDFLAGS=-Wl,--hash-style=gnu -Wl,--as-needed''

Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: nil
  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: fr_FR.utf8
  value of $XMODIFIERS: nil
  locale-coding-system: utf-8-unix
  default enable-multibyte-characters: t

Major mode: Lisp Interaction

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
  font-lock-mode: t
  blink-cursor-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
M-x r e p o r t - e m a c s <tab> <return>

Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.

Load-path shadows:
None found.

Features:
(shadow sort mail-extr message sendmail regexp-opt ecomplete rfc822 mml
easymenu mml-sec password-cache mm-decode mm-bodies mm-encode mailcap
mail-parse rfc2231 rfc2047 rfc2045 qp ietf-drums mailabbrev nnheader
gnus-util netrc time-date mm-util mail-prsvr gmm-utils wid-edit
mailheader canlock sha1 hex-util hashcash mail-utils emacsbug tooltip
ediff-hook vc-hooks lisp-float-type mwheel x-win x-dnd font-setting
tool-bar dnd fontset image fringe lisp-mode register page menu-bar
rfn-eshadow timer select scroll-bar mldrag 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 loaddefs button
minibuffer faces cus-face files text-properties overlay md5 base64
format env code-pages mule custom widget hashtable-print-readable
backquote make-network-process dbusbind system-font-setting
font-render-setting gtk x-toolkit x multi-tty emacs)

Regards,

-- 
Nicolas Goaziou