QDateTimeEdit::setTimeSpec(Qt::UTC) converts UTC QDateTime as if it was a local time

With the following code I expect the QDateTimeEdit and the QString 's' to show "1st of January 2000 12:00:00", but it shows "1st of January 2000 11:00:00":

QDateTime t(QDate(2000, 1, 1), QTime(12, 0, 0), Qt::UTC);
QDateTimeEdit edit(t);
edit.setTimeSpec(Qt::UTC);
QString s = edit.dateTime().toString();

My timezone is GMT+1. QDateTimeEdit::setTimeSpec() handles the QDateTime 't' as if it was a local time. But it is UTC. I consider this a bug.

The following code works as expected:

QDateTime t2(QDate(2000, 1, 1), QTime(12, 0, 0), Qt::UTC);
QDateTimeEdit edit2;
edit2.setTimeSpec(Qt::UTC);
edit2.setDateTime(t2);
QString s2 = edit2.dateTime().toString();