On Wednesday 17 August 2011 08:58:24 Timothy Pearson wrote:

> Something else entirely--the class names buried within the shared object
> files.  Google it. :-)  Specifically, if there are two different versions
> of a class such as "QWidget" the C++ linker cannot decide which one to
> use, both at compile time and at runtime.  This makes it impossible to use
> Qt3 and Qt4 together in a single application, and is something that is
> being corrected with the migration to TQt.

We do not try to use Qt3 and Qt4 in a single application. 
Thus there is no collision expected. Qt4 will be deprecated soon and replaced with
Qt5. It is quite difficult to catch up.
 
> > OK. I just do not understand why it is necessary to link with tqtinterface
> > non-KDE and non-Qt3 applications such as LO.
> 
> LO *is* a KDE/TDE *and* Qt3 application as soon as you set that
> --enable-kde configure flag.  Granted, the only files that will be
> compiled/linked against Qt3 and KDE/TDE are the file picker and themer,
> but they are still part of LO and still part of the resultant LO
> installation. 

It is evident that linking themer with tqtinterface is senseless: either the result
will be the same as when linking to pure Qt3 or (it you use tqt with Qt4) the theming
most likely will be broken and anyway this will compete with the 
already existing Qt4 LO themer.

> If all the other Trinity source uses the TQt C++ classes, 
> then the TDE portions of LO are among the only applications preventing
> usage of Qt3 and Qt4 together.

As I understand it, you can build Trinity against Qt3 (probably
with some calls to Qt4) or against Qt4. Thus one who uses LO can choose which themer
suits his DE better - the Qt4 themer or Qt3 themer (or there can be made auto-detection).

> As I said, I am looking into the LO build system in detail now, and will
> advise later on as to what I think is feasible.  For now we will use the
> old KDE3 integration present in LO 3.x.

My advise would be better to look on other hundreds of KDE3 applications still 
not packaged for Trinity. Say, Kdissert, KBear, Kmyfirewall, Keep, Kallery, KPhotoAlbum,
Guarddog, Guidedog, and many many others.