const T& func() const;

[Jos van den Oever]

2007/8/16, Robert Knight <robertknight at gmail.com>:
> > and what's the preformance impact?
>
> Zero surely?  For implicitly shared classes ( which KFileMetaInfo is
> ), the only cost is a pointer copy and reference increment I believe.
>
> And yes, the plan was definitely to go const T& -> T.

Exactly, I'm the one that ported it in that direction on insistence of
various other devs. Impact should be small, since QSharedDataPointer
has been optimized rather well.

Cheers,
Jos