Comment # 4 on bug 1036342 from Markos Chandras

(In reply to Dominique Leuenberger from comment #3)
> (In reply to Dominique Leuenberger from comment #2)
> > If you are running in a wayland session, then it is known that
> > gnome-session-failed does not work (if gnome-shell crashed/failed to start,
> > there is no wayland compositor and hence nothing gtk3 could paint on)
> 
> For reference, this would be
> https://bugzilla.gnome.org/show_bug.cgi?id=775337

OK thank you for the link. However I am not using wayland. I now use sddm as
display-manager and select Gnome on Xorg there and it still fails. In the
coredumpctl list I see 2 entries with identical timestamps. One is for
gnome-session-failed and the other is for Xorg. I guess what matters the most
here is the Xorg one so here it is

#0  0x00007f996bae64c7 in x86_64_fallback_frame_state (context=0x7ffd3a329180,
context=0x7ffd3a329180, fs=0x7ffd3a329270) at ./md-unwind-support.h:58
#1  0x00007f996bae64c7 in uw_frame_state_for
(context=context@entry=0x7ffd3a329180, fs=fs@entry=0x7ffd3a329270) at
../../../libgcc/unwind-dw2.c:1257
#2  0x00007f996bae8078 in _Unwind_Backtrace (trace=0x7f996dd17490
<backtrace_helper>, trace_argument=0x7ffd3a329430) at
../../../libgcc/unwind.inc:290
#3  0x00007f996dd17612 in __GI___backtrace (array=array@entry=0x7ffd3a329460,
size=size@entry=64) at ../sysdeps/x86_64/backtrace.c:110
#4  0x000000000059b71a in xorg_backtrace () at backtrace.c:125
#5  0x000000000059f4c9 in OsSigHandler (signo=11, sip=0x7ffd3a329830,
unused=<optimized out>) at osinit.c:136
#6  0x00007f996dfd4230 in <signal handler called> () at /lib64/libpthread.so.0
#7  0x0000000000000024 in  ()
#8  0x00007f996f27de3a in drmHandleEvent (fd=24, evctx=0x17e13b8) at
xf86drmMode.c:923
#9  0x000000000059ff81 in ospoll_wait (ospoll=0x179bd00, timeout=<optimized
out>) at ospoll.c:412
#10 0x0000000000598eec in WaitForSomething (are_ready=<optimized out>) at
WaitFor.c:226
#11 0x000000000043a71a in Dispatch () at dispatch.c:422
#12 0x000000000043e968 in dix_main (argc=11, argv=0x7ffd3a32af38,
envp=<optimized out>) at main.c:287
#13 0x00007f996dc3d541 in __libc_start_main (main=0x428610 <main>, argc=11,
argv=0x7ffd3a32af38, init=<optimized out>, fini=<optimized out>,
rtld_fini=<optimized out>, stack_end=0x7ffd3a32af28) at ../csu/libc-start.c:295
#14 0x000000000042864a in _start () at ../sysdeps/x86_64/start.S:120


Here are the related journal entries


Apr 27 09:09:17 aegean sddm[2284]: Running: /usr/bin/X -nolisten tcp -auth
/run/sddm/{6cae7b1a-6d96-4e50-b6a9-84a8fbb42d2d} -background none -noreset
-displayfd 19 vt7
Apr 27 09:09:17 aegean gnome-session-binary[30730]: WARNING: App
'org.gnome.SettingsDaemon.A11yKeyboard.desktop' exited with code 1
Apr 27 09:09:17 aegean gnome-session-binary[30730]: WARNING: App
'org.gnome.SettingsDaemon.Clipboard.desktop' exited with code 1
Apr 27 09:09:17 aegean gnome-session-binary[30730]: WARNING: App
'org.gnome.SettingsDaemon.Power.desktop' exited with code 1
Apr 27 09:09:17 aegean gnome-session-binary[30730]: WARNING: App
'org.gnome.SettingsDaemon.MediaKeys.desktop' exited with code 1
Apr 27 09:09:17 aegean gnome-session-binary[30730]: WARNING: App
'org.gnome.SettingsDaemon.Keyboard.desktop' exited with code 1
Apr 27 09:09:17 aegean gnome-session-binary[30730]: WARNING: App
'org.gnome.SettingsDaemon.PrintNotifications.desktop' exited with code 1
Apr 27 09:09:17 aegean polkitd[1744]: Unregistered Authentication Agent for
unix-session:5 (system bus name :1.263, object path
/org/freedesktop/PolicyKit1/AuthenticationAgent, locale en_US.UTF-8)
(disconnected from bus)
Apr 27 09:09:17 aegean gnome-session[30730]: gnome-session-binary[30730]:
WARNING: App 'org.gnome.Shell.desktop' exited with code 1
Apr 27 09:09:17 aegean gnome-session-binary[30730]: WARNING: App
'org.gnome.Shell.desktop' exited with code 1
Apr 27 09:09:17 aegean systemd-coredump[31110]: Process 30703 (X) of user 0
dumped core.