bug#17053: Emacs hangs when typing in the minibuffer

[Juanma Barranquero]

Package: emacs
Version: 24.3.50
Severity: important

Lately I've experienced a few cases of Emacs hanging while I was
typing something in the minibuffer (most likely, when using
describe-function or describe-variable).

Breakpoint 1 at 0x10f407d: file emacs.c, line 351.
Temporary breakpoint 2 at 0x1117bbc: file sysdep.c, line 854.
(gdb) bt
#0  0x771a000d in ntdll!LdrFindResource_U () from C:\Windows\SysWOW64\ntdll.dll
#1  0x7722f926 in ntdll!RtlQueryTimeZoneInformation () from
C:\Windows\SysWOW64\ntdll.dll
#2  0x2cb03a9e in ?? ()
#3  0x00000000 in ?? ()

Lisp Backtrace:
"read-from-minibuffer" (0x88e280)
"completing-read-default" (0x88e5c0)
"completing-read" (0x88e6d4)
"byte-code" (0x88e980)
"call-interactively" (0x88ec84)
"electric-helpify" (0x88efc8)
"electric-describe-function" (0x88f314)
"call-interactively" (0x88f520)
"command-execute" (0x88f85c)
(gdb) thread 1
[Switching to thread 1 (Thread 9436.0x1f1c)]
#0  0x771b015d in ntdll!RtlEnableEarlyCriticalSectionEventCreation ()
from C:\Windows\SysWOW64\ntdll.dll
(gdb) bt
#0  0x771b015d in ntdll!RtlEnableEarlyCriticalSectionEventCreation ()
from C:\Windows\SysWOW64\ntdll.dll
#1  0x771b015d in ntdll!RtlEnableEarlyCriticalSectionEventCreation ()
from C:\Windows\SysWOW64\ntdll.dll
#2  0x75f415e9 in WaitForMultipleObjectsEx () from
C:\Windows\syswow64\KernelBase.dll
#3  0x00000004 in ?? ()
#4  0x0088d5d4 in ?? ()
#5  0x74d919fc in KERNEL32!GetVolumePathNamesForVolumeNameA () from
C:\Windows\syswow64\kernel32.dll
#6  0x0088d5d4 in ?? ()
#7  0x75fa086a in USER32!MessageBoxA () from C:\Windows\syswow64\user32.dll
#8  0x00000004 in ?? ()
#9  0x7efde000 in ?? ()
#10 0x75fa0b69 in USER32!DdeNameService () from C:\Windows\syswow64\user32.dll
#11 0x00000050 in ?? ()
#12 0x0088d800 in ?? ()
#13 0x01230585 in sys_select (nfds=4, rfds=0x88dab0, wfds=0x0,
efds=0x0, timeout=0x88daa0, ignored=0x0) at w32proc.c:2095
#14 0x011cedf0 in wait_reading_process_output (time_limit=300,
nsecs=0, read_kbd=-1, do_display=true, wait_for_cell=58361890,
wait_proc=0x0, just_wait_proc=0) at process.c:4590
#15 0x0100f07c in sit_for (timeout=1200, reading=true,
display_option=1) at dispnew.c:5805
#16 0x010fae99 in read_char (commandflag=1, map=88463302,
prev_event=58361890, used_mouse_menu=0x88ddc3, end_time=0x0) at
keyboard.c:2806
#17 0x01107b45 in read_key_sequence (keybuf=0x88dee0, bufsize=30,
prompt=58361890, dont_downcase_last=false,
can_return_switch_frame=true, fix_current_buffer=true,
    prevent_redisplay=false) at keyboard.c:9079
#18 0x010f81f5 in command_loop_1 () at keyboard.c:1449
#19 0x01181567 in internal_condition_case (bfun=0x10f7e75
<command_loop_1>, handlers=58413410, hfun=0x10f76db <cmd_error>) at
eval.c:1354
#20 0x010f7b2a in command_loop_2 (ignore=58361890) at keyboard.c:1174
#21 0x01180b14 in internal_catch (tag=58491330, func=0x10f7b06
<command_loop_2>, arg=58361890) at eval.c:1118
#22 0x010f7a91 in command_loop () at keyboard.c:1145
#23 0x010f7278 in recursive_edit_1 () at keyboard.c:777
#24 0x0112fcb7 in read_minibuf (map=60501390, initial=58361890,
prompt=88113425, expflag=false, histvar=58514978, histpos=0,
defalt=19415857, allow_props=false,
    inherit_input_method=false) at minibuf.c:664
#25 0x01130500 in Fread_from_minibuffer (prompt=88113425,
initial_contents=58361890, keymap=60501390, sys_read=58361890,
hist=58361890, default_value=19415857,
    inherit_input_method=58361890) at minibuf.c:954
#26 0x01184796 in Ffuncall (nargs=8, args=0x88e27c) at eval.c:2841
#27 0x011c523c in exec_byte_code (bytestr=19819529, vector=19819549,
maxdepth=72, args_template=8200, nargs=8, args=0x88e5e0) at
bytecode.c:919
#28 0x01184de9 in funcall_lambda (fun=19819509, nargs=8,
arg_vector=0x88e5c0) at eval.c:2983
#29 0x01184843 in Ffuncall (nargs=9, args=0x88e5bc) at eval.c:2864
#30 0x01131aa6 in Fcompleting_read (prompt=88113425,
collection=58363917, predicate=58416770, require_match=58361922,
initial_input=58361890, hist=58361890, def=19415857,
    inherit_input_method=58361890) at minibuf.c:1671
#31 0x0118480a in Ffuncall (nargs=8, args=0x88e6d0) at eval.c:2848
#32 0x011c523c in exec_byte_code (bytestr=59036001, vector=58755997,
maxdepth=48, args_template=58361890, nargs=0, args=0x0) at
bytecode.c:919
#33 0x011c468c in Fbyte_code (bytestr=59036001, vector=58755997,
maxdepth=48) at bytecode.c:482
#34 0x011832cd in eval_sub (form=62324278) at eval.c:2191
#35 0x01182b06 in Feval (form=62324278, lexical=58361890) at eval.c:2003
#36 0x0117c374 in Fcall_interactively (function=61011266,
record_flag=58361890, keys=58383221) at callint.c:345
#37 0x0118465c in Ffuncall (nargs=2, args=0x88ec80) at eval.c:2822
#38 0x011c523c in exec_byte_code (bytestr=62094657, vector=86347781,
maxdepth=64, args_template=2052, nargs=1, args=0x88efcc) at
bytecode.c:919
#39 0x01184de9 in funcall_lambda (fun=86233021, nargs=1,
arg_vector=0x88efc8) at eval.c:2983
#40 0x01184843 in Ffuncall (nargs=2, args=0x88efc4) at eval.c:2864
#41 0x011c523c in exec_byte_code (bytestr=62103985, vector=86348181,
maxdepth=8, args_template=0, nargs=0, args=0x88f314) at bytecode.c:919
#42 0x01184de9 in funcall_lambda (fun=86348197, nargs=0,
arg_vector=0x88f314) at eval.c:2983
#43 0x01184843 in Ffuncall (nargs=1, args=0x88f310) at eval.c:2864
#44 0x01184069 in apply1 (fn=86242690, arg=58361890) at eval.c:2581
#45 0x0117c4ce in Fcall_interactively (function=86242690,
record_flag=58361890, keys=58383221) at callint.c:378
#46 0x0118465c in Ffuncall (nargs=4, args=0x88f51c) at eval.c:2822
#47 0x011c523c in exec_byte_code (bytestr=19837209, vector=19837229,
maxdepth=52, args_template=4100, nargs=1, args=0x88f860) at
bytecode.c:919
#48 0x01184de9 in funcall_lambda (fun=19837189, nargs=1,
arg_vector=0x88f85c) at eval.c:2983
#49 0x01184843 in Ffuncall (nargs=2, args=0x88f858) at eval.c:2864
#50 0x011840f2 in call1 (fn=58408098, arg1=86242690) at eval.c:2614
#51 0x010f84d9 in command_loop_1 () at keyboard.c:1556
#52 0x01181567 in internal_condition_case (bfun=0x10f7e75
<command_loop_1>, handlers=58413410, hfun=0x10f76db <cmd_error>) at
eval.c:1354
#53 0x010f7b2a in command_loop_2 (ignore=58361890) at keyboard.c:1174
#54 0x01180b14 in internal_catch (tag=58408770, func=0x10f7b06
<command_loop_2>, arg=58361890) at eval.c:1118
#55 0x010f7ae2 in command_loop () at keyboard.c:1153
#56 0x010f7278 in recursive_edit_1 () at keyboard.c:777
#57 0x010f7434 in Frecursive_edit () at keyboard.c:845
#58 0x010f5637 in main (argc=2, argv=0x9e1c40) at emacs.c:1646