Is Qt4.5 required for trunk now?

[Alexander Neundorf]

On Sunday 08 February 2009, Andreas Pakulat wrote:
> On 07.02.09 17:25:06, Sebastian Kügler wrote:
> > On Saturday 07 February 2009 17:00:51 Thiago Macieira wrote:
> > > Andreas Pakulat wrote:
> > > >On 07.02.09 14:15:18, Sebastian Kügler wrote:
> > > >> Building is one, working is another. I'm aware of at least one patch
> > > >> that will cause regressions with Qt 4.4. It removes layouting hacks
> > > >> to make QGraphicsLayouts update properly with 4.4. Those bugs have
> > > >> been fixed in Qt 4.5.
> > > >>
> > > >> I've also committed a similar patch today, but it was for code
> > > >> that's still in playground anyway, so it doesn't really count.
> > > >>
> > > >> Just to mention that we're in fact already relying on 4.5, even if
> > > >> it will still compile with 4.4.
> > > >
> > > >Which is wrong, IMHO. Those changes should be reverted and applied
> > > > again when we require Qt4.5. Note that I'd be fine with requiring it
> > > > from next monday on or something, its just that I'd like to not
> > > > update my qt-copy until kdelibs requires Qt4.5 and so far thats not
> > > > the case.
> > >
> > > That's wishful thinking.
> > >
> > > The moment that people start developing with Qt 4.5, those kinds of
> > > changes will creep in. Even unintended, people will write code that
> > > depends on the 4.5 behaviour and the bugfixes present in it.
> >
> > Indeed. Besides that, some of the hacks that have been removed actually
> > break things on Qt 4.5 (because they relied on bugy behaviour in Qt 4.4),

Can you detect at runtime which version of Qt it is and then use one or the 
other path ?
(...without looking at any code)
This could then also make KDE 4.2.>0 work with Qt 4.5.

> > so it's not as easy as just reverting them...
>
> Then maybe we should (in the future anyway) simply update kdelibs
> requirement when qt-copy is updated to a new (non-bugfix) version and more
> importantly also announce that requirement change?

Yes, and please also announce it before it is actually required, so people 
have some time to update, instead of suddenly being forced to rebuild qt.

Alex