infloop when removing character

[Simon Josefsson]

I have seen this a few times now, the last time I removed a
parenthesis at the end of the line with backspace, I recall it hanging
in similar situations before.

I did 'cvs upd' but there were no changes in src/, so I believe my
emacs is fairly up to date.

Program received signal SIGTSTP, Stopped (user).
scan_newline (start=1086115847, start_byte=513066, limit=1, limit_byte=1,
    count=-525, allow_quit=0) at search.c:809
809                   while (--cursor != ceiling_addr && *cursor != '\n')
(gdb) n
814                       if (++count == 0)
(gdb)
809                   while (--cursor != ceiling_addr && *cursor != '\n')
(gdb)
814                       if (++count == 0)
(gdb)
809                   while (--cursor != ceiling_addr && *cursor != '\n')
(gdb)
814                       if (++count == 0)
(gdb)
809                   while (--cursor != ceiling_addr && *cursor != '\n')
(gdb)
814                       if (++count == 0)
(gdb)
809                   while (--cursor != ceiling_addr && *cursor != '\n')
(gdb)
814                       if (++count == 0)
(gdb)
809                   while (--cursor != ceiling_addr && *cursor != '\n')
(gdb)
814                       if (++count == 0)
(gdb)
809                   while (--cursor != ceiling_addr && *cursor != '\n')
(gdb)
814                       if (++count == 0)
(gdb)
809                   while (--cursor != ceiling_addr && *cursor != '\n')
(gdb)
814                       if (++count == 0)
(gdb)
809                   while (--cursor != ceiling_addr && *cursor != '\n')
(gdb)
814                       if (++count == 0)
(gdb)
809                   while (--cursor != ceiling_addr && *cursor != '\n')
(gdb) p cursor
$6 = (
    unsigned char *) 0x40bd3335 "\nnnimap: Quickly checking mailbox 
INBOX.gnu-prog-disc\nnnimap: Quickly checking mailbox INBOX.libtool\nnnimap: 
Quickly checking mailbox INBOX.sent-mail.2002.12\nnnimap: Quickly checking 
mailbox INBOX.sen"...
(gdb) p ceiling_addr
$7 = (unsigned char *) 0x40bcd007 ""
(gdb) p count
$8 = -516
(gdb) n
814                       if (++count == 0)
(gdb)
809                   while (--cursor != ceiling_addr && *cursor != '\n')
(gdb)
814                       if (++count == 0)
(gdb)
809                   while (--cursor != ceiling_addr && *cursor != '\n')
(gdb)
814                       if (++count == 0)
(gdb)
809                   while (--cursor != ceiling_addr && *cursor != '\n')
(gdb) c
Continuing.
 
Program received signal SIGTSTP, Stopped (user).
0x08140f15 in scan_newline (start=1086115847, start_byte=513066, limit=1,
    limit_byte=1, count=-9641, allow_quit=0) at search.c:809
809                   while (--cursor != ceiling_addr && *cursor != '\n')
(gdb) p count
$9 = -9641
(gdb) bt full
#0  0x08140f15 in scan_newline (start=1086115847, start_byte=513066, limit=1,
    limit_byte=1, count=-9641, allow_quit=0) at search.c:809
        direction = -1
        cursor = (
    unsigned char *) 0x40c4446c "% completed...\ngnus-agent-expire cleared 
download flag on article 4681 as the cached article file is 
missing.\ngnus-agent-expire detected a missing NOV entry.  Run 
gnus-agent-regenerate-group to restor"...
        base = (unsigned char *) 0x40c4a431 ""
        ceiling = 1086604396
        ceiling_addr = (unsigned char *) 0x40bcd007 ""
        old_immediate_quit = 0
#1  0x08096cdc in message_dolog (m=0x81a5be4 "", nbytes=-1073748704, nlflag=1,
    multibyte=0) at xdisp.c:6279
        this_bol = -1073748704
        this_bol_byte = -1073748689
        prev_bol = 513022
        prev_bol_byte = 513022
        dup = 137550656
        oldbuf = (struct buffer *) 0x9416958
        oldpoint = 674330184
        oldbegv = 674330204
        oldzv = 674330224
        old_windows_or_buffers_changed = 523342
---Type <return> to continue, or q <return> to quit---

        point_at_end = 1
        zv_at_end = 1
        old_deactivate_mark = 405673668
        tem = 137550656
        gcpro1 = {
  next = 0x0,
  var = 0x0,
  nvars = -1073748424
}
#2  0x080969b4 in message_log_maybe_newline () at xdisp.c:6146
No locals.
#3  0x0810bbf1 in cmd_error_internal (data=1500288016, context=0xbfffe5d0 "")
    at keyboard.c:1226
        stream = 139876064
        kill_emacs_p = 0
#4  0x0810ba7f in cmd_error (data=1500288016) at keyboard.c:1174
        old_level = 405673668
        old_length = 405673668
        macroerror = "address@hidden@address@hidden"
#5  0x08163ab4 in internal_condition_case (bfun=0x810bde4 <command_loop_1>,
    handlers=405784756, hfun=0x810b9d8 <cmd_error>) at eval.c:1323
        val = 1086604396
---Type <return> to continue, or q <return> to quit---
        c = {
  tag = 405673668,
  val = 1500288016,
  next = 0xbfffe780,
  gcpro = 0x0,
  jmp = {{
      __jmpbuf = {0, 1, -1073747736, -1073748152, -1073748432, 135674529},
      __mask_was_saved = 0,
      __saved_mask = {
        __val = {1079928080, 139543144, 0, 0, 110932256, 3221219136,
          1073813208, 3221219016, 1079943696, 1079557216, 1078462232,
          1079671240, 0 <repeats 18 times>, 1073812652, 1073813208}
      }
    }},
  backlist = 0x0,
  handlerlist = 0x0,
  lisp_eval_depth = 0,
  pdlcount = 2,
  poll_suppress_count = 1,
  interrupt_input_blocked = 0,
  byte_stack = 0x0
}
        h = {
---Type <return> to continue, or q <return> to quit---
  handler = 405784756,
  var = 405673668,
  chosen_clause = 405673716,
  tag = 0xbfffe660,
  next = 0x0
}
#6  0x0810bcba in command_loop_2 () at keyboard.c:1292
        val = 1086604396
#7  0x081636a5 in internal_catch (tag=1086604396,
    func=0x810bc9c <command_loop_2>, arg=405673668) at eval.c:1094
        c = {
  tag = 405746020,
  val = 405673668,
  next = 0x0,
  gcpro = 0x0,
  jmp = {{
      __jmpbuf = {0, 1, -1073747736, -1073747864, -1073748112, 135673466},
      __mask_was_saved = 0,
      __saved_mask = {
        __val = {0, 139542136, 1079924840, 5, 429496729, 0, 1080614752,
          139543144, 139543144, 3221218984, 1079928080, 139543144, 0,
          3221219016, 1079943727, 139543144, 1079882577, 3221219016, 0,
          1074309576, 674330284, 0, 405919036, 3221219400, 135614975,
---Type <return> to continue, or q <return> to quit---
          405919036, 674330284, 405673668, 137303856, 1479460504, 405673668,
          674330284}
      }
    }},
  backlist = 0x0,
  handlerlist = 0x0,
  lisp_eval_depth = 0,
  pdlcount = 2,
  poll_suppress_count = 1,
  interrupt_input_blocked = 0,
  byte_stack = 0x0
}
#8  0x0810bc70 in command_loop () at keyboard.c:1271
No locals.
#9  0x0810b7b4 in recursive_edit_1 () at keyboard.c:987
        val = 0
#10 0x0810b8c4 in Frecursive_edit () at keyboard.c:1043
        buffer = 1086604396
#11 0x0810a225 in main (argc=3, argv=0xbfffeb84) at emacs.c:1666
        dummy = 1073812652
        stack_bottom_variable = -65 '\277'
        do_initial_setlocale = 1
        skip_args = 0
---Type <return> to continue, or q <return> to quit---
        rlim = {
  rlim_cur = 18446744073709551615,
  rlim_max = 18446744073709551615
}
        no_loadup = 0
        junk = 0x0
(gdb)
(gdb)