Packaging guideline for a library using either Qt4 or Qt5

[Kevin Kofler]

Laurent Rineau wrote:
> Do you suggest that the upstream project should have a different library
> name when it is compiled with Qt4 and Qt5?

Yes, see Rex Dieter's reply.

> Why is that better than the following suggestion:
> 
>   /usr/lib64/libQGLViewer.so -> libQGLViewer.so.2.5.1
>   /usr/lib64/libQGLViewer.so.2.5.1
>   /usr/lib64/Qt5/libQGLViewer.so -> libQGLViewer.so.2.5.1
>   /usr/lib64/Qt5/libQGLViewer.so.2.5.1

Because that suggestion relies on rpath (yuck!), -L flags and similar hacks 
to select the correct version. It also tries to establish a standard 
"/usr/lib64/Qt5" that has no uptake from other packages, the other upstreams 
are renaming their libraries (e.g., all the KDE ones, and even Qt itself).

The Qt 5 version should be something like:
/usr/lib64/libQGLViewer-qt5.so → libQGLViewer-qt5.so.2.5.1
/usr/lib64/libQGLViewer-qt5.so.2.5.1

(Please do not rename the Qt 4 version, for backwards compatibility.)

And the libQGLViewer-qt5.so name should really get upstreamed.

        Kevin Kofler