bug#5809: 23.1.94; cross-reference by anchor yields in accurate position

[Eli Zaretskii <eliz@gnu.org>]

 emacs -Q
 C-u C-h i /path/to/elisp RET
 g Handling Errors RET

Now press TAB repeatedly to move point to the "Definition of signal"
hyperlink, and press RET => you will find yourself in the "Signaling
Errors" node, but 3 lines above the place where the description of
`signal' begins.

I see this on GNU/Linux with Texinfo 4.12 and on MS-Windows with
Texinfo 4.8.  (But I don't think makeinfo is the culprit, see below.)

This is a regression from Emacs 22.3, which behaves as expected.
Emacs 23.1 has the same problem as the current pretest.  (Both 22.3
and 23.1 were tested with the same Info files as 23.1.94.)  The trunk
has the same problem as well.


In GNU Emacs 23.1.94.1 (i386-mingw-nt5.1.2600)
 of 2010-03-12 on HOME-C4E4A596F7
Windowing system distributor `Microsoft Corp.', version 5.1.2600
configured using `configure --with-gcc (3.4)'

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: ENU
  value of $XMODIFIERS: nil
  locale-coding-system: cp1255
  default enable-multibyte-characters: t

Major mode: Mail

Minor modes in effect:
  shell-dirtrack-mode: t
  diff-auto-refine-mode: t
  flyspell-mode: t
  desktop-save-mode: t
  show-paren-mode: t
  display-time-mode: t
  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
  temp-buffer-resize-mode: t
  line-number-mode: t
  abbrev-mode: t

Recent input:
C-z C-z C-z C-z C-z C-z <help-echo> <help-echo> <help-echo> 
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo> 
<help-echo> <help-echo> <help-echo> <switch-frame> 
l <return> <help-echo> C-x = <switch-frame> <help-echo> 
<help-echo> <help-echo> <help-echo> <switch-frame> 
<help-echo> <help-echo> <help-echo> <C-home> C-x C-x 
<switch-frame> <help-echo> <help-echo> <help-echo> 
<help-echo> <help-echo> <help-echo> <help-echo> <help-echo> 
<help-echo> <help-echo> <switch-frame> <switch-frame> 
<help-echo> <help-echo> <help-echo> <switch-frame> 
<help-echo> <help-echo> <help-echo> <help-echo> <switch-frame> 
C-x C-s C-x 4 a H o w SPC t o SPC r e - t h r o w SPC 
a SPC s i g n a l SPC c a u g h t SPC b y SPC c i o 
<backspace> o n d i t i o n - c a s e <C-left> <C-left> 
<right> <delete> <M-right> . C-x C-s <help-echo> <M-end> 
<help-echo> <help-echo> <M-home> <up> <up> C-SPC <down> 
<down> <down> M-w <M-end> C-y <up> <up> <up> <delete> 
<delete> <delete> <down> <delete> SPC <left> <up> <return> 
<up> <return> <up> E x p l a i n SPC h o w SPC t o 
SPC r e - t h r o w SPC a SPC s i g n a l . <right> 
<down> <down> <down> <delete> C-x C-s C-x # C-x k <return> 
<M-home> C-x k <return> <C-next> <C-next> <C-next> 
<C-next> <C-next> <C-next> <C-next> <C-next> <C-next> 
<C-next> <M-end> r C-c C-y C-x C-x C-SPC <down> <down> 
<down> <up> C-w <down> <down> <down> <down> C-SPC <next> 
<down> <down> <down> <down> <down> <down> <down> <down> 
<down> C-w M-z M-z M-z M-z <down> <down> <C-end> C-w 
<return> I S-SPC a d d e d SPC t h i s SPC t o SPC 
t h e SPC E L i s p SPC m a n u a l . <return> <C-home> 
C-c C-s <switch-frame> <switch-frame> M-x r e p o p 
<backspace> r t - e m <tab> <return>

Recent messages:
Saving file d:/gnu/bzr/emacs/emacs-23/doc/lispref/ChangeLog...
Wrote d:/gnu/bzr/emacs/emacs-23/doc/lispref/ChangeLog
When done with a buffer, type C-x #
Mark set [2 times]
Saving file d:/usr/tmp/bzr_log.59l73j...
Wrote d:/usr/tmp/bzr_log.59l73j
Mark set [5 times]
Sending...
Added to d:/usr/eli/rmail/SENT.MAIL
Sending...done

Load-path shadows:
None found.

Features:
(shadow emacsbug debug rmailedit tramp-imap assoc tramp-gw tramp-fish
tramp-cache tramp-ftp tramp-cmds tramp shell format-spec tramp-compat
trampver iso-transl compare-w whitespace diff-mode texinfo crm
thingatpt rmailout mule-util ebuff-menu electric descr-text dabbrev pp
help-mode view auth-source message ecomplete rfc822 mml mml-sec
password-cache mm-decode mm-bodies mm-encode mailcap mail-parse
rfc2231 rfc2047 rfc2045 qp ietf-drums nnheader gnus-util netrc mm-util
mail-prsvr gmm-utils wid-edit mailheader canlock hashcash smtpmail
multi-isearch mailalias mailabbrev sendmail conf-mode newcomment
ld-script sh-script executable dired-x dired-aux dired tcl generic
nxml-uchnm rng-xsd xsd-regexp rng-cmpct rng-nxml rng-valid rng-loc
rng-uri rng-parse nxml-parse rng-match rng-dt rng-util rng-pttrn
nxml-ns nxml-mode nxml-outln nxml-rap nxml-util nxml-glyph nxml-enc
xmltok sgml-mode arc-mode archive-mode parse-time python-21 python
comint ring org-wl org-w3m org-vm org-rmail org-mhe org-mew org-irc
org-jsinfo org-infojs org-html org-exp org-exp-blocks org-agenda
org-info org-gnus org-bibtex org-bbdb org byte-opt bytecomp
byte-compile advice help-fns advice-preload org-footnote org-src
org-list org-faces org-compat org-macs time-date noutline outline
easy-mmode flyspell ispell add-log jka-compr vc-bzr sha1 hex-util
make-mode info cc-mode cc-fonts easymenu cc-menus cc-cmds cc-styles
cc-align cc-engine cc-vars cc-defs regexp-opt vc-cvs rmailsum rmail
mail-utils desktop server filecache saveplace generic-x paren battery
time tooltip ediff-hook vc-hooks lisp-float-type mwheel dos-w32
disp-table ls-lisp w32-win w32-vars 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 multi-tty
emacs)