Comment 4 for bug 1635772

Hello,
I'm affected by the same. Problem appears after adding CalDAV calendar.

In a fresh install of eOS 0.4:

~$ gdb maya-calendar
GNU gdb (Ubuntu 7.11.1-0ubuntu1~16.04) 7.11.1
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Reading symbols from maya-calendar...(no debugging symbols found)...done.
(gdb) run
Starting program: /usr/bin/maya-calendar
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[New Thread 0x7fffe0b1d700 (LWP 6624)]
[New Thread 0x7fffe031c700 (LWP 6625)]
[INFO 20:35:32.504337] Application.vala:155: Calendar version: 0.4.0.2
[INFO 20:35:32.504563] Application.vala:157: Kernel version: 4.4.0-57-generic
[New Thread 0x7fffdd752700 (LWP 6628)]
[New Thread 0x7fffdcf51700 (LWP 6629)]
[New Thread 0x7fffcffff700 (LWP 6631)]
[New Thread 0x7fffcf7fe700 (LWP 6632)]
[New Thread 0x7fffccf75700 (LWP 6633)]
[New Thread 0x7fffbffff700 (LWP 6639)]
[FATAL 20:35:33.060245] maya_util_is_all_day: assertion 'dtend != NULL' failed
[FATAL 20:35:33.060356] [GLib] g_date_time_format: assertion 'datetime != NULL' failed

Thread 1 "maya-calendar" received signal SIGSEGV, Segmentation fault.
0x00007ffff52de87c in g_date_time_to_timezone () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
(gdb)