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

[Paul Harrison]

On 14/05/2020 20:58, Peter Bennett wrote:

> On 5/13/20 7:34 PM, Paul Harrison wrote:
>
>> I don't believe this bug is specific to MythTV but more a regression 
>> in libmysqlclient you can easily reproduce it using this simple Qt 
>> test app.
>>
>>
>> #include <QApplication>
>> #include <QSqlDatabase>
>> #include <QString>
>> #include <QDebug>
>>
>> void cause_segfault()
>> {
>>   {
>>     QSqlDatabase db = QSqlDatabase::addDatabase("QMYSQL");
>>     db.setDatabaseName("mythconverg");
>>     db.setUserName("mythtv");
>>     db.setHostName("192.168.1.32");
>>     db.setPassword("xxxxxxxx");
>>     db.open();
>>     db.close();
>>   }
>>   auto name = QSqlDatabase::database().connectionName();
>>   qDebug() << "About to remove database";
>>   QSqlDatabase::removeDatabase(name);
>>   qDebug() << "Removed database";
>> }
>>
>> int main(int argc, char *argv[])
>> {
>>   QApplication a(argc, argv);
>>   cause_segfault();
>>   return -1;
>> }
>>
>> Paul H.
>>
>>
>>
> I tested installing the prior version of libmysqlclient21. That 
> resolves the issue, as is mentioned in the ticket.
>
> https://vitux.com/how-to-downgrade-packages-on-ubuntu/
>
> Also libmysqlclientdev needs to be downgraded, if building from source.
>
> Peter
>
>

It's also possible to reproduce the crash using just libmysqlclient 
directly without using Qt.

https://bugs.launchpad.net/ubuntu/+source/mysql-8.0/+bug/1877504/comments/10


Paul H.