bug#24119: 25.1; suspend-frame "freezes" Emacs under i3-wm

[Eli Zaretskii <eliz@gnu.org>]

> From: Benjamin Riefenstahl <b.riefenstahl@turtle-trading.net>
> Cc: 24119@debbugs.gnu.org
> Date: Sun, 31 Jul 2016 16:57:58 +0200
> 
> Eli Zaretskii writes:
> > Thanks.  Can you please recreate the problem in an unoptimized build,
> > and post a backtrace from that?  Backtraces from optimized builds are
> > frequently misleading and/or missing vital information.
> 
> Sure, see below.
> 
>     #0  0xb6331dc3 in ?? () from /lib/i386-linux-gnu/i686/cmov/libc.so.6
>     No symbol table info available.
>     #1  0xb632a533 in pselect () from /lib/i386-linux-gnu/i686/cmov/libc.so.6
>     No symbol table info available.
>     #2  0x08280216 in xg_select (fds_lim=9, rfds=0xbfa5c204, wfds=0xbfa5c184, efds=0x0, 
>         timeout=0xbfa5c178, sigmask=0x0) at xgselect.c:113
>             all_rfds = {
>               fds_bits = {464, 0 <repeats 31 times>}
>             }
>             all_wfds = {
>               fds_bits = {0 <repeats 32 times>}
>             }
>             tmo = {
>               tv_sec = 167607947, 
>               tv_nsec = -1079656808
>             }
>         [...]
>     #3  0x0823ec78 in wait_reading_process_output (time_limit=30, nsecs=0, read_kbd=-1, do_display=true, 
>         wait_for_cell=0, wait_proc=0x0, just_wait_proc=0) at process.c:4831
>             process_skipped = false
>             channel = 1024
>             nfds = 0
>             Available = {
>               fds_bits = {80, 0 <repeats 31 times>}
>             }
>             Writeok = {
>               fds_bits = {0 <repeats 32 times>}
>             }
>         [...]
>     #4  0x080629f2 in sit_for (timeout=122, reading=true, display_option=1) at dispnew.c:5762
>             sec = 30
>             nsec = 0
>             do_display = true
>     #5  0x0816e7ef in read_char (commandflag=1, map=167511299, prev_event=0, used_mouse_menu=0xbfa5c5df, 
>         end_time=0x0) at keyboard.c:2714

This looks like Emacs is just waiting for input.  Could you look at
the status of the various threads in the process, and tell what you
see?

Thanks.