Hi zeljko
I met this problem in slackware-current/qt5, from 5.7 to 5.9.3.
after any program exit, include lazarus ide, there will be AV and some callstack dumped.
1.8.0 and trunk(r59141) is the same.
following is something maybe helpful
----------------------------------BEGIN----------------------------------------------------------
(gdb) r
Starting program: /root/work/devel/2/nxdlinux/mgr/nlmgr
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib64/libthread_db.so.1".
QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to '/tmp/runtime-root'
[New Thread 0x7fffeab8a700 (LWP 1847)]
QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to '/tmp/runtime-root'
[New Thread 0x7fffe0c61700 (LWP 1848)]
[New Thread 0x7fffdbfff700 (LWP 1849)]
[New Thread 0x7fffd9a88700 (LWP 1852)]
Thread 1 "nlmgr" received signal SIGSEGV, Segmentation fault.
0x00007ffff6eca979 in _dl_catch_error () from /lib64/libc.so.6
(gdb) bt
#0 0x00007ffff6eca979 in _dl_catch_error () at /lib64/libc.so.6
#1 0x00007ffff79b45c5 in _dlerror_run () at /lib64/libdl.so.2
#2 0x00007ffff79b3fff in dlclose () at /lib64/libdl.so.2
#3 0x00007ffff5150e03 in () at /usr/lib64/libQt5Core.so.5
#4 0x00007ffff514ae6d in () at /usr/lib64/libQt5Core.so.5
#5 0x00007ffff513bd92 in () at /usr/lib64/libQt5Core.so.5
#6 0x00007ffff513bed9 in () at /usr/lib64/libQt5Core.so.5
#7 0x00007ffff518a1a3 in QObject::~QObject() () at /usr/lib64/libQt5Core.so.5
#8 0x00007ffff5a96d49 in () at /usr/lib64/libQt5Gui.so.5
#9 0x00007ffff6daddd8 in __run_exit_handlers () at /lib64/libc.so.6
#10 0x00007ffff6dade2a in () at /lib64/libc.so.6
#11 0x00007ffff6d94031 in __libc_start_main () at /lib64/libc.so.6
#12 0x0000000000000000 in ()
-----------------------------------END--------------------------------------------------------------
I'm not sure to report an issue, you may have a look first.
If you need more details or some test, just give me a message.
Thanks you and lazarus team.