different symbols for liblightdm-qt on different architectures

[Yves-Alexis Perez]

Hi,

I've uploaded lightdm 1.18.2 to Debian, but it seems that there are updated symbols in the library but only on non-intel architectures. That means it fails to build (https://buildd.debian.org/status/package.php?p=lightdm&suite=sid).

That discrepancy only appeared in 1.18.2 which I find a bit surprising, and I wonder if it's not a sign of a problem in the library.

[Yves-Alexis Perez (corsac)]

The symbols differences are only in destructors, it seems:

QDBusError::~QDBusError()
QByteArray::~QByteArray()
QHash<int, QByteArray>::~QHash()
QString::~QString()

[Yves-Alexis Perez (corsac)]

It actually seems linked to the g++ version: the symbol changes only happen with g++-6, not g++-5.

[Robert Ancell (robert-ancell)]

Based on my experience of previous C++ packages it's not unexpected for different symbols to be generated. I don't think it's a reflection of the upstream code (there's no changes that are conditional on architecture).