segmentation fault in w32bdf.c

[Chris Moore]

Since I started making daily builds of Emacs on my Windows XP box
using the latest code from CVS I've seen a few crashes.  As a result
I've taken to running Emacs inside gdb to capture the stack when it
crashes.  Here's the first stack trace I've been able to capture.
The Emacs process had been running successfully for a couple of days,
I had used CVS, VM, ERC, ange-ftp, e-shell and a bunch of other stuff
all without problems.

At the time of the crash I was trying to drag the mouse over a URL
that somebody had typed in an IRC channel that I was connected to
using ERC.  The URL had been highlighted by ERC, and when Emacs
crashed there was one of those 'tool tips' popped up on the screen
telling me I could click the link to open it, or some such.

I've been unable to reproduce the crash, but I wasn't short of
memory, or doing anything unusual at the time.

I'm using version 1.19 of w32bdf.c - it was modified just 5 days ago:

  revision 1.19
  date: 2003/10/02 23:07:28;  author: jasonr;  state: Exp;  lines: +1 -0
  * w32fns.c (w32_load_system_font): Clear all members of FONTP before
  filling them.
  * w32bdf.c (w32_load_bdf_font): Likewise.

Here's the gdb output.  I'll leave the gdb session open for a while
in case anybody wants me to type something at it...

  C:\chris\bin>gdb C:/chris/emacs/src/emacs/bin/emacs.exe
  GNU gdb 5.1.1 (mingw experimental)
  Copyright 2002 Free Software Foundation, Inc.
  GDB is free software, covered by the GNU General Public License, and you are
  welcome to change it and/or distribute copies of it under certain conditions.
  Type "show copying" to see the conditions.
  There is absolutely no warranty for GDB.  Type "show warranty" for details.
  This GDB was configured as "mingw32"...

  Program received signal SIGSEGV, Segmentation fault.
  get_cached_font_char (fontp=0x2174b22c, strchr=32) at w32bdf.c:343
  343       pch = fontp->chtbl[BDF_FIRST_OFFSET(index)];
  (gdb) where
  #0  get_cached_font_char (fontp=0x2174b22c, strchr=32) at w32bdf.c:343
  #1  0x01158711 in get_bitmap_with_cache (fontp=0x2174b22c, strchr=32)
      at w32bdf.c:541
  #2  0x01158a02 in w32_BDF_TextOut (fontp=0x2174b22c, hdc=0x54010cd5, left=45,
      top=389, text=0x82f1c0 " ", dim=2, bytelen=0, fixed_pitch_size=0)
      at w32bdf.c:672
  #3  0x0114225a in w32_text_out (s=0x82f1d0, x=45, y=389, chars=0x82f1c0,
      nchars=1) at w32term.c:1128
  #4  0x0114287d in x_draw_glyph_string_foreground (s=0x82f1d0) at 
w32term.c:1505
  #5  0x0114471d in x_draw_glyph_string (s=0x82f1d0) at w32term.c:2381
  #6  0x0104d22b in draw_glyphs (w=0x24e9e00, x=52, row=0x210dc3c,
      area=TEXT_AREA, start=5, end=6, hl=DRAW_CURSOR, overlaps_p=0)
      at xdisp.c:17546
  #7  0x010527f8 in draw_phys_cursor_glyph (w=0x24e9e00, row=0x210dc3c,
      hl=DRAW_CURSOR) at xdisp.c:18976
  #8  0x01052f5d in display_and_set_cursor (w=0x24e9e00, on=1, hpos=5, vpos=27,
      x=35, y=378) at xdisp.c:19172
  #9  0x011413e4 in x_update_window_end (w=0x24e9e00, cursor_on_p=1,
      mouse_face_overwritten_p=1) at w32term.c:540
  #10 0x01084995 in update_window (w=0x24e9e00, force_p=0) at dispnew.c:4199
  #11 0x01084409 in update_window_tree (w=0x24e9e00, force_p=0) at 
dispnew.c:3885
  #12 0x010842f9 in update_frame (f=0x17b5a00, force_p=0, inhibit_hairy_id_p=0)
      at dispnew.c:3822
  #13 0x0103fcea in redisplay_internal (preserve_echo_area=1) at xdisp.c:10050
  #14 0x01008afa in read_char (commandflag=1, nmaps=3, maps=0x82fb3c,
      prev_event=561229828, used_mouse_menu=0x82fb78) at keyboard.c:2493
  #15 0x0101098a in read_key_sequence (keybuf=0x82fca0, bufsize=30,
      prompt=561229828, dont_downcase_last=0, can_return_switch_frame=1,
      fix_current_buffer=1) at keyboard.c:8825
  #16 0x01006d14 in command_loop_1 () at keyboard.c:1504
  #17 0x0101d857 in internal_condition_case (bfun=0x1006ba0 <command_loop_1>,
      handlers=561351188, hfun=0x1006630 <cmd_error>) at eval.c:1333
  #18 0x0100695d in command_loop_2 () at keyboard.c:1292
  #19 0x0101d39f in internal_catch (tag=561303492,
      func=0x1006930 <command_loop_2>, arg=561229828) at eval.c:1094
  #20 0x01006907 in command_loop () at keyboard.c:1271
  #21 0x010063e0 in recursive_edit_1 () at keyboard.c:987
  #22 0x0100650b in Frecursive_edit () at keyboard.c:1043
  #23 0x01003117 in main (argc=1, argv=0xa23df0) at emacs.c:1666
  #24 0x01001165 in __mingw_CRTStartup ()
  #25 0x01001013 in mainCRTStartup ()
  #26 0x77e814c7 in _libmsvcrt_a_iname ()
  (gdb)

Chris.












In GNU Emacs 21.3.50.1 (i386-mingw-nt5.1.2600)
 of 2003-10-07 on CHRISLAP
configured using `configure --with-gcc (3.2)'

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: ENG
  locale-coding-system: iso-latin-1
  default-enable-multibyte-characters: t

Major mode: VM Summary

Minor modes in effect:
  auto-compression-mode: t
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  erc-button-mode: t
  erc-ring-mode: t
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  erc-track-mode: t
  show-paren-mode: t
  iswitchb-mode: t
  mouse-wheel-mode: t
  global-font-lock-mode: t
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