quit gdb causes 100% cpu [24.0.95]

[Neal Becker]

fedora 16 x86_64
repeatable: quite gdb causes emacs to use 100% cpu.
Attaching now gdb to emacs process, shows:

0  0x0000003d0ca440ff in g_main_context_prepare () from /lib64/libglib-2.0.so.0
#1  0x0000003d0ca44e6d in ?? () from /lib64/libglib-2.0.so.0
#2  0x0000003d0ca453a0 in g_main_context_pending () from /lib64/libglib-2.0.so.0
#3  0x00000000004ecd68 in xg_select (max_fds=16, rfds=0x7ffffa440580, 
wfds=0x7ffffa440600, 
    efds=0x0, timeout=0x7ffffa4407d0) at 
/usr/src/debug/emacs-24.0.95/src/xgselect.c:52
#4  0x00000000005b6653 in wait_reading_process_output (time_limit=30, 
microsecs=0, read_kbd=
    -1, do_display=1, wait_for_cell=12012034, wait_proc=<optimized out>, 
just_wait_proc=0)
    at /usr/src/debug/emacs-24.0.95/src/process.c:4608
#5  0x0000000000421244 in sit_for (timeout=120, reading=1, do_display=1)
    at /usr/src/debug/emacs-24.0.95/src/dispnew.c:6063
#6  0x000000000050d2ed in read_char (commandflag=1, nmaps=3, 
maps=0x7ffffa440c90, 
    prev_event=12012034, used_mouse_menu=0x7ffffa440e20, end_time=0x0)
    at /usr/src/debug/emacs-24.0.95/src/keyboard.c:2692
#7  0x000000000050e067 in read_key_sequence (keybuf=0x7ffffa440e80, 
prompt=12012034, 
    dont_downcase_last=0, can_return_switch_frame=1, fix_current_buffer=1, 
bufsize=30)
    at /usr/src/debug/emacs-24.0.95/src/keyboard.c:9328
#8  0x000000000050fd45 in command_loop_1 ()
    at /usr/src/debug/emacs-24.0.95/src/keyboard.c:1449
#9  0x0000000000575e76 in internal_condition_case (bfun=0x50fb70 
<command_loop_1>, handlers=
    12064322, hfun=0x504980 <cmd_error>) at 
/usr/src/debug/emacs-24.0.95/src/eval.c:1515
#10 0x0000000000502e7e in command_loop_2 (ignore=<optimized out>)
    at /usr/src/debug/emacs-24.0.95/src/keyboard.c:1160
#11 0x0000000000575d58 in internal_catch (tag=Cannot access memory at address 
0xffffffffffffffe1
)
    at /usr/src/debug/emacs-24.0.95/src/eval.c:1272
#12 0x0000000000504457 in command_loop ()
    at /usr/src/debug/emacs-24.0.95/src/keyboard.c:1139
#13 recursive_edit_1 () at /usr/src/debug/emacs-24.0.95/src/keyboard.c:759
#14 0x000000000050478c in Frecursive_edit ()
    at /usr/src/debug/emacs-24.0.95/src/keyboard.c:823
#15 0x000000000041611d in main (argc=1, argv=<optimized out>)
    at /usr/src/debug/emacs-24.0.95/src/emacs.c:1715