SIGSEGV on exiting application under QT5.6

[zeljko]

That's same thing:
#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

Crash comes from glibc (or from wrong Qt implementation when unloading library)

[baldzhang]

http://users.telenet.be/Jan.Van.hijfte/qtforfpc/fpcqt4.html
downloaded demo from here, change qt4 -> qt5, 2 program compile passed.
SIGSEGV is the same...

[baldzhang]

tested at slackware 14.2 x86-64, glibc-2.23
upgraded qt5 5.9.3 from here:
https://slackware.pkgs.org/14.2/slackel-x86_64/qt5-5.9.3-x86_64-1dj.txz.html

it's ok, so looks like this issue is related to glibc for 90%...
but arch is running with glibc 2.26 also and it's ok there.

[zeljko]

Probably arch uses some custom glibc patch, or different could be distro combination of glibc and gcc. Really don't know. Maybe one must write pure simple Qt c++ app to see if crash occurs.

[baldzhang]

tested ok on ubuntu and arch, detail version info:

ubuntu 17.10
   qt 5.9.1
   glibc 2.26
   gcc 7.2.0

arch
   qt 5.10.0
   glibc 2.26
   gcc 7.3.0


will try to rebuild glibc and test.

[baldzhang]

ok, I give up, after build glibc 3 times, I totally no idea how to do now.

[zeljko]

Fedora 26 uses glibc 2.25 and there we have problem. glibc 2.23, 2.24 works fine on fedoras.
If you don't have problems with 2.26 then it's obvious where bug is.

[baldzhang]

build and upgrade glibc 2.27, it's ok now