When declaring a function prepended by a Q_INVOKABLE, the moc is only able to generate an invokable function in the meta object when not using a placeholder type specifier auto.

E.g. the following declaration is being generated correctly

Q_INVOKABLE 
qint32 find(const QString &);

but this ones is not:

Q_INVOKABLE 
auto find(const QString &) -> qint32;

Reading the docs, it is stated that the macro should be placed in front of the return type. So even trying weird things like

 auto find(const QString &) -> Q_INVOKABLE qint32;

does not work.

There is a simple workaround by not using auto in the first place. But in order to provide a clean interface definition in the header file it would be great to be able to use auto.