bug#12466: 24.2; crash on OS X 10.7 in [EmacsView windowDidResize]

[Eli Zaretskii]

> From: Michael McCracken <michael.mccracken@gmail.com>
> Date: Tue, 18 Sep 2012 09:23:17 -0700
> 
> This is a recurring issue, after several days of usage, emacs crashes
> when resizing a frame.
> 
> Specifically, this is on the main screen of a two-screen setup, and I
> was resizing one of two frames.

This is not a crash, this is an abort:

> 9   libsystem_c.dylib                 0x00007fff906afa7a abort + 143
> 10  org.gnu.Emacs                     0x00000001001235fd Fsignal + 125
> 11  org.gnu.Emacs                     0x0000000100123b89 xsignal + 9
> 12  org.gnu.Emacs                     0x0000000100124015 xsignal3 + 37
> 13  org.gnu.Emacs                     0x0000000100155703 scan_lists + 1539

scan_lists called xsignal3, which called abort, here:

  if (gc_in_progress || waiting_for_input)
    emacs_abort ();

So the question is: why did scan_lists signal an error, or why was
waiting_for_input non-zero at that time (I see no evidence that
gc_in_progress could be non-zero, but maybe some bug could have caused
that)?

The call to scan_lists seem to have been originated by evaluation of
some Lisp by display code that was invoked to handle the resize:

> 74  org.gnu.Emacs                     0x0000000100022e0f safe_call + 159
> 75  org.gnu.Emacs                     0x0000000100022e7e safe_call1 + 30
> 76  org.gnu.Emacs                     0x0000000100022fe8 
> handle_fontified_prop + 360
> 77  org.gnu.Emacs                     0x000000010002d92e handle_stop + 126
> 78  org.gnu.Emacs                     0x0000000100040068 
> next_element_from_buffer + 1272
> 79  org.gnu.Emacs                     0x0000000100034401 
> get_next_display_element + 81
> 80  org.gnu.Emacs                     0x0000000100036039 
> move_it_in_display_line_to + 409
> 81  org.gnu.Emacs                     0x000000010003a251 move_it_to + 321
> 82  org.gnu.Emacs                     0x000000010003b781 move_it_vertically + 
> 65
> 83  org.gnu.Emacs                     0x0000000100059b45 Fwindow_end + 357