bug#16510: Assertion failure during GC while displaying etc/HELLO

[Juanma Barranquero <lekktu@gmail.com>]

Package: Emacs
Version: 24.3.50

I can reproduce it with many different fonts, like Droid Sans Mono and
Courier Prime, but not with Courier New.

emacs -Q -fn "Linux Libertine Mono-10"
C-h h

alloc.c:2908: Emacs fatal error: assertion failed: valid_font_driver
(((struct font *) vector)->driver)

Breakpoint 1, terminate_due_to_signal (sig=22,
backtrace_limit=2147483647) at emacs.c:351
351       signal (sig, SIG_DFL);
(gdb) bt
#0  terminate_due_to_signal (sig=22, backtrace_limit=2147483647) at emacs.c:351
#1  0x01161e05 in die (msg=0x149acb0 "valid_font_driver (((struct font
*) vector)->driver)", file=0x149a8a0 "alloc.c", line=2908) at
alloc.c:6761
#2  0x0115c594 in cleanup_vector (vector=0x683a620) at alloc.c:2908
#3  0x0115c6b4 in sweep_vectors () at alloc.c:2959
#4  0x01161b51 in gc_sweep () at alloc.c:6649
#5  0x0115fbc0 in Fgarbage_collect () at alloc.c:5572
#6  0x010ee027 in maybe_gc () at lisp.h:4518
#7  0x0117fdd7 in Ffuncall (nargs=2, args=0x88cdf0) at eval.c:2757
#8  0x0117d28e in internal_condition_case_n (bfun=0x117fd1f
<Ffuncall>, nargs=2, args=0x88cdf0, handlers=58333250, hfun=0x1026bac
<safe_eval_handler>) at eval.c:1427
#9  0x01026ccc in safe_call (nargs=2, func=58465986) at xdisp.c:2563
#10 0x01026d09 in safe_call1 (fn=58465986, arg=60058702) at xdisp.c:2579
#11 0x01026d25 in safe_eval (sexpr=60058702) at xdisp.c:2587
#12 0x0105fa30 in display_mode_element (it=0x88d048, depth=3,
field_width=0, precision=0, elt=60058710, props=58333218, risky=0) at
xdisp.c:21636
#13 0x0105ff81 in display_mode_element (it=0x88d048, depth=1,
field_width=0, precision=0, elt=60158702, props=58333218, risky=0) at
xdisp.c:21717
#14 0x0105eaed in display_mode_line (w=0x3ad1690
<__register_frame_info+61675152>, face_id=MODE_LINE_FACE_ID,
format=60158710) at xdisp.c:21234
#15 0x0105e688 in display_mode_lines (w=0x3ad1690
<__register_frame_info+61675152>) at xdisp.c:21177
#16 0x0104cef6 in redisplay_window (window=61675157,
just_this_one_p=false) at xdisp.c:16373
#17 0x010446e3 in redisplay_window_0 (window=61675157) at xdisp.c:14054
#18 0x0117d04c in internal_condition_case_1 (bfun=0x10446ad
<redisplay_window_0>, arg=61675157, handlers=58316006, hfun=0x1044689
<redisplay_window_error>) at eval.c:1369
#19 0x01044670 in redisplay_windows (window=61675157) at xdisp.c:14034
#20 0x010436a6 in redisplay_internal () at xdisp.c:13633
#21 0x01041723 in redisplay () at xdisp.c:12919
#22 0x010f645b in read_char (commandflag=1, map=60697070,
prev_event=58333218, used_mouse_menu=0x88f793, end_time=0x0) at
keyboard.c:2563
#23 0x01103902 in read_key_sequence (keybuf=0x88f8b0, bufsize=30,
prompt=58333218, dont_downcase_last=false,
can_return_switch_frame=true, fix_current_buffer=true,
    prevent_redisplay=false) at keyboard.c:9071
#24 0x010f3f6d in command_loop_1 () at keyboard.c:1445
#25 0x0117cf39 in internal_condition_case (bfun=0x10f3bed
<command_loop_1>, handlers=58384674, hfun=0x10f3453 <cmd_error>) at
eval.c:1345
#26 0x010f38a2 in command_loop_2 (ignore=58333218) at keyboard.c:1170
#27 0x0117c4e6 in internal_catch (tag=58380034, func=0x10f387e
<command_loop_2>, arg=58333218) at eval.c:1109
#28 0x010f385a in command_loop () at keyboard.c:1149
#29 0x010f2ff0 in recursive_edit_1 () at keyboard.c:777
#30 0x010f31ac in Frecursive_edit () at keyboard.c:841
#31 0x010f13a5 in main (argc=4, argv=0x993018) at emacs.c:1643

Lisp Backtrace:
"Automatic GC" (0x1537e1c)
"eval" (0x88cdf4)
"redisplay_internal (C function)" (0x1537e1c)
(gdb)