[mythtv] [mythtv-commits] mythtv commit: r16790 - in trunk byjanne

[Anduin Withers]

There is also a Qt 4 bug in the MySQL driver that causes database open
failures to crash (the way we currently use MSqlQuery).

The following code should reproduce it:

#include <QApplication>
#include <QSqlDatabase>
#include <QSqlQuery>

int main(int argc, char *argv[]) {
    QApplication qapp(argc, argv);
    QSqlDatabase qsdb = QSqlDatabase::addDatabase("QMYSQL", "atest");
    qsdb.setHostName("test");
    qsdb.setDatabaseName("test");
    qsdb.setUserName("test");
    qsdb.setPassword("test");
    qsdb.open();

    QSqlQuery query(qsdb);
}

Backtraces that end in:

#0  0x00002aaaaf7e865d in QMYSQLResult::cleanup (this=0x649c60)
    at ../../../sql/drivers/mysql/qsql_mysql.cpp:410
#1  0x00002aaaaf7e89a4 in ~QMYSQLResult (this=0x649c6d)
    at ../../../sql/drivers/mysql/qsql_mysql.cpp:381
#2  0x000000339fc10b4e in ~QSqlQuery (this=<value optimized out>)
    at kernel/qsqlquery.cpp:249
#3  MSqlQuery::~MSqlQuery

may be suspect.

> mythfrontend -p segfaults

This seems to be the cause.

I've created a Qt 4 bug for this issue. We should find some workaround as
the travel time to a Qt 4 near you probably prohibits anything else.

The actual bug is in QMYSQLResult::cleanup which uses d->mysql even if it
was made invalid in QMYSQLDriver::open.

--
Anduin Withers