bug#27098: 26.0.50; Wrong display of negative Lisp_Object values

[Eli Zaretskii]

To reproduce, run Emacs under GDB with src/.gdbinit in effect, then
display a Lisp_Object value.  On my system, where Lis_Object values
are 64-bit values with the sign bit set, I see something like this:

  (gdb) print current_buffer->name_
  $1 = XIL(0x-7ffffffffe851450)

which displays the negative sign after the 0x prefix.  But even if we
remove the minus, the value after it is misleading:

  (gdb) print current_buffer->name_.i
  $2 = -9223372036829942864
  (gdb) print/x current_buffer->name_.i
  $3 = 0x80000000017aebb0

Is it possible to tweak the Python parts of src/.gdbinit to display
XIL(0x80000000017aebb0), not XIL(0x-7ffffffffe851450)?

In GNU Emacs 26.0.50 (build 531, i686-pc-mingw32)
 of 2017-05-27 built on HOME-C4E4A596F7
Repository revision: 6f63c7cb6a02d913d195410e4df85fad5832db06
Windowing system distributor 'Microsoft Corp.', version 5.1.2600
Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.

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

Configured features:
XPM JPEG TIFF GIF PNG RSVG SOUND NOTIFY ACL GNUTLS LIBXML2 ZLIB
TOOLKIT_SCROLL_BARS MODULES

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
  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 subr-x puny seq byte-opt gv
bytecomp byte-compile cconv cl-loaddefs pcase cl-lib dired
dired-loaddefs format-spec rfc822 mml easymenu mml-sec password-cache
epa derived epg epg-config gnus-util rmail rmail-loaddefs mm-decode
mm-bodies mm-encode mail-parse rfc2231 mailabbrev gmm-utils mailheader
sendmail rfc2047 rfc2045 ietf-drums mm-util mail-prsvr mail-utils
time-date mule-util 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 menu-bar rfn-eshadow isearch timer select
scroll-bar mouse jit-lock font-lock syntax facemenu font-core
term/tty-colors frame 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 minibuffer cl-preloaded nadvice loaddefs
button faces cus-face macroexp files text-properties overlay sha1 md5
base64 format env code-pages mule custom widget hashtable-print-readable
backquote w32notify w32 multi-tty make-network-process emacs)

Memory information:
((conses 16 101600 11038)
 (symbols 56 21118 1)
 (miscs 48 42 108)
 (strings 16 21005 4762)
 (string-bytes 1 595878)
 (vectors 16 14676)
 (vector-slots 8 480299 6161)
 (floats 8 54 93)
 (intervals 40 269 104)
 (buffers 864 11))