bug#9106: 24.0.50; ./configure causes massive recompilation

[Eli Zaretskii]

Invocation of the `configure' script causes recompilation of many
source files, even though nothing has really changed.

It looks like the cause is lib/Makefile which states that several
generated headers in that directory depend on config.status.  So each
`configure' causes those headers to be regenerated, which in turn
triggers many files using those headers to be recompiled.

This is annoying, as building Emacs even on a modern system takes a
significant amount of time (about 3 minutes on this box, whose details
see below).  Can this annoyance be removed, please?


In GNU Emacs 24.0.50.22 (x86_64-unknown-linux-gnu, GTK+ Version 2.20.1)
 of 2011-07-17 on fencepost
configured using `configure  '--with-gif=no' '--with-tiff=no''

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: nil
  locale-coding-system: nil
  default enable-multibyte-characters: t

Major mode: RMAIL

Minor modes in effect:
  display-time-mode: t
  show-paren-mode: t
  savehist-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
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t

Recent input:
B ESC O A ESC O A ESC O A C-x C-f C h a n g TAB RET 
ESC [ 5 ~ ESC [ 5 ~ ESC [ 6 ~ ESC [ 6 ~ ESC [ 6 ~ ESC 
[ 6 ~ ESC O B ESC O B ESC O B ESC O B ESC O B ESC O 
B ESC O B ESC O B ESC O B ESC O B ESC O B ESC O B ESC 
O C ESC O C ESC O C ESC O C ESC O C ESC O C ESC O C 
ESC O C ESC O C ESC O C ESC O C ESC O C ESC O C ESC 
O C ESC O C ESC O C ESC O C ESC O C ESC O C ESC O C 
ESC O C ESC O C ESC O C ESC O C ESC O C ESC O C ESC 
O C ESC O C ESC O C ESC O B ESC O B ESC O B ESC O B 
ESC O B ESC O B ESC O B ESC O B ESC O B ESC O B ESC 
O B ESC O B ESC O B ESC O B ESC O B ESC O A ESC O A 
ESC O A ESC O A C-x b I N B TAB RET C-u g m a i l . 
n e w RET m e m a c s - d e v e l @ g n u . o r g DEL 
DEL DEL DEL DEL DEL DEL DEL SPC DEL @ g n u . o r g 
ESC O B ESC ~ C-x 5 o ESC x r e p o r t - e m TAB 
RET

Recent messages:
scroll-down-command: Beginning of buffer [2 times]
Getting mail from /srv/data/home/e/eliz/mail.new...
Counting new messages...
Counting messages...60
Counting new messages...done (70)
Saving file /home/e/eliz/INBOX...
Wrote /home/e/eliz/INBOX [2 times]
Computing summary lines...done
70 new messages read
Modification-flag cleared

Load-path shadows:
None found.

Features:
(shadow emacsbug sendmail flyspell ispell add-log vc-bzr cc-mode
cc-fonts cc-guess cc-menus cc-cmds cc-styles cc-align cc-engine
cc-vars cc-defs regexp-opt qp rmailsum rmailmm message format-spec
rfc822 mml easymenu mml-sec mm-decode mm-bodies mm-encode mailabbrev
gmm-utils mailheader mail-parse rfc2231 rmail rfc2047 rfc2045
ietf-drums mm-util mail-prsvr mail-utils time paren cus-start cus-load
time-date savehist saveplace tooltip ediff-hook vc-hooks
lisp-float-type mwheel x-win x-dnd tool-bar dnd fontset image fringe
lisp-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 loaddefs button faces cus-face files text-properties
overlay sha1 md5 base64 format env code-pages mule custom widget
hashtable-print-readable backquote make-network-process
dynamic-setting font-render-setting move-toolbar gtk x-toolkit x
multi-tty emacs)