[mythtv-users] segfault in libmysqlclient.so.21

[Peter Bennett]

On 5/12/20 6:43 AM, Paul Harrison wrote:
> John just to be clear can you confirm you are seeing the same issue?
>
> This particular bug affects all MythTV apps that use the database but 
> only causes a segfault when exiting the apps. The problem appears to 
> be caused by an update to libmysqlclient. Did you recently have an 
> update to that?
>
> What distro and version are you using? I'm using Kubuntu 19.10.
>
> There is another bug in MariaDB 10.4 
> (https://forum.mythtv.org/viewtopic.php?f=2&t=3720) I just want to be 
> sure we are not confusing the two issues.
>
>
> Paul H.

I am also seeing this now after installing Ubuntu 20.04 and building master.

Also using mariadb - perhaps we should be using a mariadb client library 
instead of the mysql one (e.g. "libmariadb3 - MariaDB database client 
library" instead of "libmysqlclient21 - MySQL database client library")

FWIW Here is the backtrace

Core was generated by `mythbackend'.
Program terminated with signal SIGSEGV, Segmentation fault.
#0  0x00007f19a640930f in ?? () from 
/lib/x86_64-linux-gnu/libmysqlclient.so.21
[Current thread is 1 (Thread 0x7f19a9233340 (LWP 2987))]
(gdb) bt
#0  0x00007f19a640930f in  () at /lib/x86_64-linux-gnu/libmysqlclient.so.21
#1  0x00007f19a640e823 in  () at /lib/x86_64-linux-gnu/libmysqlclient.so.21
#2  0x00007f19a63ac243 in mysql_server_end () at 
/lib/x86_64-linux-gnu/libmysqlclient.so.21
#3  0x00007f19b6ab10ee in  () at 
/usr/lib/x86_64-linux-gnu/qt5/plugins/sqldrivers/libqsqlmysql.so
#4  0x00007f19b6ab110d in  () at 
/usr/lib/x86_64-linux-gnu/qt5/plugins/sqldrivers/libqsqlmysql.so
#5  0x00007f19b61b05fb in  () at /lib/x86_64-linux-gnu/libQt5Sql.so.5
#6  0x00007f19b61b088e in QSqlDatabase::~QSqlDatabase() () at 
/lib/x86_64-linux-gnu/libQt5Sql.so.5
#7  0x00007f19b61b2901 in  () at /lib/x86_64-linux-gnu/libQt5Sql.so.5
#8  0x00007f19b5ab345c in QHashData::free_helper(void 
(*)(QHashData::Node*)) () at /lib/x86_64-linux-gnu/libQt5Core.so.5
#9  0x00007f19b61b0b4c in  () at /lib/x86_64-linux-gnu/libQt5Sql.so.5
#10 0x00007f19b61b0cb7 in  () at /lib/x86_64-linux-gnu/libQt5Sql.so.5
#11 0x00007f19b5c28852 in qt_call_post_routines() () at 
/lib/x86_64-linux-gnu/libQt5Core.so.5
#12 0x00007f19b5c289a2 in QCoreApplication::~QCoreApplication() () at 
/lib/x86_64-linux-gnu/libQt5Core.so.5
#13 0x000055a1780912ee in main(int, char**) (argc=1, 
argv=0x7fff14ac53d8) at main.cpp:88