bug#4863: 23.1; etags gets confused on GCC sources

[Aldy Hernandez <aldyh@redhat.com>]

When running etags on the following source distilled from GCC sources,
no foobar1 symbol is generated.

extern VEC(tree,gc) *ctor_to_vec (tree);

void
foobar1 ()
{
}



In GNU Emacs 23.1.1 (x86_64-redhat-linux-gnu, GTK+ Version 2.16.6)
 of 2009-09-29 on x86-6.fedora.phx.redhat.com
Windowing system distributor `The X.Org Foundation', version 11.0.10603901
configured using `configure  '--build=x86_64-redhat-linux-gnu' '--host=x86_64-redhat-linux-gnu' '--target=x86_64-redhat-linux-gnu' '--program-prefix=' '--prefix=/usr' '--exec-prefix=/usr' '--bindir=/usr/bin' '--sbindir=/usr/sbin' '--sysconfdir=/etc' '--datadir=/usr/share' '--includedir=/usr/include' '--libdir=/usr/lib64' '--libexecdir=/usr/libexec' '--localstatedir=/var' '--sharedstatedir=/var/lib' '--mandir=/usr/share/man' '--infodir=/usr/share/info' '--with-dbus' '--with-gif' '--with-jpeg' '--with-png' '--with-rsvg' '--with-tiff' '--with-xft' '--with-xpm' '--with-x-toolkit=gtk' 'build_alias=x86_64-redhat-linux-gnu' 'host_alias=x86_64-redhat-linux-gnu' 'target_alias=x86_64-redhat-linux-gnu' 'CFLAGS=-DMAIL_USE_LOCKF -O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector 
 --param=ssp-buffer-size=4 -m64 -mtune=generic''

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: nil
  value of $XMODIFIERS: @im=none
  locale-coding-system: nil
  default-enable-multibyte-characters: t

Major mode: C/l

Minor modes in effect:
  diff-auto-refine-mode: t
  erc-list-mode: t
  erc-menu-mode: t
  erc-autojoin-mode: t
  erc-ring-mode: t
  erc-networks-mode: t
  erc-pcomplete-mode: t
  erc-track-mode: t
  erc-track-minor-mode: t
  erc-match-mode: t
  erc-button-mode: t
  erc-fill-mode: t
  erc-stamp-mode: t
  erc-netsplit-mode: t
  erc-irccontrols-mode: t
  erc-noncommands-mode: t
  erc-move-to-prompt-mode: t
  erc-readonly-mode: t
  tooltip-mode: t
  tool-bar-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
  global-auto-composition-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  column-number-mode: t
  line-number-mode: t
  transient-mark-mode: t
  abbrev-mode: t

Recent input:
SPC d o e s <backspace> <backspace> <backspace> <backspace> 
<backspace> <backspace> <backspace> <backspace> <backspace> 
S-SPC ( s o m e t i m e s ) SPC o r SPC <left> <left> 
<left> <left> <right> o n SPC g c c SPC s o u r c e 
s SPC <end> d o e s SPC n o SPC <backspace> b o d y 
SPC e l s e SPC c a r e ? <return> i s SPC t h e r 
e SPC a SPC b u g z i l l a SPC p l a c e SPC i SPC 
c a n SPC r e p o r t SPC t h i s ? SPC <return> n 
o SPC t a g s ? SPC SPC w h a t SPC i s SPC t h e SPC 
m a t t e r SPC w i t h SPC y o u . <backspace> ? SPC 
SPC h o w SPC d o SPC <backspace> SPC y ' a l l SPC 
n a v i g a t e SPC g c c SPC s o u r c e s . <return> 
w e l l , SPC i SPC u s e SPC g r e p SPC l a t e l 
y , SPC o b v i o u s l y . . . <return> <help-echo> 
<down-mouse-1> <mouse-1> M-x r e p o r t - e m <tab> 
<return> C-g <down-mouse-1> <mouse-1> <help-echo> m 
<backspace> / m e SPC l o o k s SPC u p SPC g n u SPC 
i d u t i l s <return> <help-echo> <down-mouse-1> <mouse-1> 
M-x r e p o r t - e m <tab> <return>

Recent messages:
Saving file /home/aldyh/tmp/a.c...
Wrote /home/aldyh/tmp/a.c
Saving file /home/aldyh/tmp/a.c...
Wrote /home/aldyh/tmp/a.c
Undo!
Saving file /home/aldyh/tmp/a.c...
Wrote /home/aldyh/tmp/a.c
Saving file /home/aldyh/tmp/a.c...
Wrote /home/aldyh/tmp/a.c
Mark set [2 times]
Quit