bug#49478: 28.0.50; Produce preloaded *.eln files when ABI hash changes

[Eli Zaretskii <eliz@gnu.org>]

Currently, whenever the native-compilation ABI hash changes, the *.eln
files of the preloaded Lisp packages are not automatically
regenerated, unless NATIVE_FULL_AOT is defined.  This requires
annoying manual procedures to regenerate the *.eln files in the new
subdirectory of native-lisp/.

This feature request is to augment the Makefiles with a rule that
would automatically regenerate the preloaded *.eln files when the ABI
hash changes.  The idea is to write comp-abi-hash to a file (using
move-if-change), and when that changes, to trigger the recompilation
of the preloaded Lisp packages via the Make machinery.



In GNU Emacs 28.0.50 (build 171, i686-pc-mingw32)
 of 2021-07-09 built on HOME-C4E4A596F7
Repository revision: c73bc89e663290649e4c9a89b15f96b885bcd736
Repository branch: master
Windowing system distributor 'Microsoft Corp.', version 5.1.2600
System Description: Microsoft Windows XP Service Pack 3 (v5.1.0.2600)

Configured using:
 'configure -C --prefix=/d/usr --with-wide-int --with-native-compilation
 --enable-checking=yes,glyphs 'CFLAGS=-O0 -gdwarf-4 -g3''

Configured features:
ACL GIF GMP GNUTLS HARFBUZZ JPEG JSON LCMS2 LIBXML2 MODULES NATIVE_COMP
NOTIFY W32NOTIFY PDUMPER PNG RSVG SOUND THREADS TIFF TOOLKIT_SCROLL_BARS
XPM ZLIB

Important settings:
  value of $LANG: ENU
  locale-coding-system: cp1255

Major mode: Lisp Interaction

Minor modes in effect:
  tooltip-mode: t
  global-eldoc-mode: t
  eldoc-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
  blink-cursor-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

Load-path shadows:
None found.

Features:
(shadow sort mail-extr emacsbug message rmc puny dired dired-loaddefs
rfc822 mml mml-sec epa derived epg epg-config gnus-util rmail
rmail-loaddefs auth-source eieio eieio-core eieio-loaddefs
password-cache json map text-property-search time-date mm-decode
mm-bodies mm-encode mail-parse rfc2231 mailabbrev gmm-utils mailheader
sendmail rfc2047 rfc2045 ietf-drums mm-util mail-prsvr mail-utils comp
comp-cstr warnings subr-x rx cl-seq cl-macs cl-extra help-mode seq
byte-opt gv cl-loaddefs cl-lib bytecomp byte-compile cconv iso-transl
tooltip eldoc electric uniquify ediff-hook vc-hooks lisp-float-type
mwheel dos-w32 ls-lisp disp-table term/w32-win w32-win w32-vars
term/common-win tool-bar dnd fontset image regexp-opt fringe
tabulated-list replace newcomment text-mode elisp-mode lisp-mode
prog-mode register page tab-bar menu-bar rfn-eshadow isearch easymenu
timer select scroll-bar mouse jit-lock font-lock syntax font-core
term/tty-colors frame minibuffer cl-generic cham georgian utf-8-lang
misc-lang vietnamese tibetan thai tai-viet lao korean japanese eucjp-ms
cp51932 hebrew greek romanian slovak czech european ethiopic indian
cyrillic chinese composite charscript charprop case-table epa-hook
jka-cmpr-hook help simple abbrev obarray cl-preloaded nadvice button
loaddefs faces cus-face macroexp files window text-properties overlay
sha1 md5 base64 format env code-pages mule custom widget
hashtable-print-readable backquote threads w32notify w32 lcms2 multi-tty
make-network-process native-compile emacs)

Memory information:
((conses 16 78462 7957)
 (symbols 48 8976 1)
 (strings 16 24365 2851)
 (string-bytes 1 714099)
 (vectors 16 16227)
 (vector-slots 8 267082 11652)
 (floats 8 28 63)
 (intervals 40 267 112)
 (buffers 888 11))