Unused parameters in slots

[ePharaoh]

I have declared a slot as follows,

class Shell {
    Q_OBJECT
    public slots:
       void treeExpanded (const QModelIndex &index);
}

class Shell {
    Q_OBJECT
    public slots:
       void treeExpanded (const QModelIndex &index);
}

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Now, I don't have a use for the index parameter. Gcc gives a warning in this case, saying index is unused. (I try to keep my code free of warnings )

Now, if I don't want that warning I can say,

class Shell {
    Q_OBJECT
    public slots:
       void treeExpanded (__attribute__((unused)) const QModelIndex &index);
}

class Shell {
    Q_OBJECT
    public slots:
       void treeExpanded (__attribute__((unused)) const QModelIndex &index);
}

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The warning goes off but the moc generated bad code. I get a compile error for the moc_Shell.cpp

moc_Shell.cpp: In member function `virtual int
Shell::qt_metacall(QMetaObject::Call, int, void**)':
moc_Shell.cpp:78: error: parse error before `*' token

Is there any solution to this? Thanks...