[mythtv-users] Mythfrontend seg faults

[lists at murrell.ca]

Hi Marc.

----- "Marc Randolph" <mrand at pobox.com> wrote:

> If your segfault is creating a core dump (a file with the word core
> in
> it, usually in the home directory of where a program is executed),
> then you don't need to use "run" on the gdb command line.  Instead,
> you can analyze that core file.

I didn't see a core dump, but have found a way to continue.  The end of the "run" sequence in gdb ends with this:


"Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0xb288e730 (LWP 4640)]
0xad7e1724 in QMutexPool::get () from /usr/lib/libqt-mt.so.3"

so it appears to be an issue with QT.  Following the rest of that example usage, I did a backtrace, which output the following:

--- START ---
#0  0xad7e1724 in QMutexPool::get () from /usr/lib/libqt-mt.so.3
#1  0xad4ed6ba in QMetaObjectCleanUp::QMetaObjectCleanUp ()
   from /usr/lib/libqt-mt.so.3
#2  0xad893679 in ?? () from /usr/lib/libqt-mt.so.3
#3  0xad893add in ?? () from /usr/lib/libqt-mt.so.3
#4  0xad3fbb6c in _init () from /usr/lib/libqt-mt.so.3
#5  0xb7fd0404 in ?? () from /lib/ld-linux.so.2
#6  0xb7fd0534 in ?? () from /lib/ld-linux.so.2
#7  0xb7fd446b in ?? () from /lib/ld-linux.so.2
#8  0xb7fd0036 in ?? () from /lib/ld-linux.so.2
#9  0xb7fd3c1e in ?? () from /lib/ld-linux.so.2
#10 0xb4e7abec in ?? () from /lib/tls/i686/cmov/libdl.so.2
#11 0xb7fd0036 in ?? () from /lib/ld-linux.so.2
#12 0xb4e7b01c in ?? () from /lib/tls/i686/cmov/libdl.so.2
#13 0xb4e7ab21 in dlopen () from /lib/tls/i686/cmov/libdl.so.2
#14 0xb52b91c7 in ?? () from /usr/lib/libQtCore.so.4
#15 0xb52b352c in ?? () from /usr/lib/libQtCore.so.4
#16 0xb52b3758 in QLibrary::resolve () from /usr/lib/libQtCore.so.4
#17 0xb67cf094 in MythPlugin::init () from /usr/lib/libmyth-0.22.so.0
#18 0xb67cf7cf in MythPluginManager::init_plugin ()
   from /usr/lib/libmyth-0.22.so.0
#19 0xb67d191d in MythPluginManager::MythPluginManager ()
   from /usr/lib/libmyth-0.22.so.0
#20 0x0806e81c in ?? ()
#21 0xb4f0a775 in __libc_start_main () from /lib/tls/i686/cmov/libc.so.6
#22 0x080613e1 in ?? ()
--- END ---

I am not sure which "frame" would be the one to follow through with, but that is probably a moot point since it does not appear to be a MythTV issue, but rather a QT one.  If you wish to pursue this further, I am willing, but understand that it is probably beyond your scope of support :-)

> I did find someone that is running a combined FE/BE on r21651 today
> with no segfault.

Were they running Mythbuntu 9.04 as well and "upgraded" to weekly builds/trunk?

-Alan