A USE flag to use system QT libraries instead of bundled would be helpful. For example the VirtualBox bundled qt libraries don't support QGtkStyle, so you can't use native gtk looks. I *think* that the distro-specific packages that Oracle provides use the distro's system libraries (at least for Fedora), so that means it is somewhat supported by upstream. I haven't observed any problems using system libraries, but for safety the qt-static USE flag should be enabled by default. Reproducible: Always Steps to Reproduce: 1. Select "GTK+" (Which means QGtkStyle) under GUI Style in "qtconfig" 2. Open VirtualBox, QGtkStyle does not work, it uses a "basic" gtk style. Close it. 3. rm or mv /opt/VirtualBox/libQt* 4. Use system libraries: ln -s /usr/lib64/qt4/libQtCore.so.4 /opt/VirtualBox/libQtCoreVBox.so.4 ln -s /usr/lib64/qt4/libQtGui.so.4 /opt/VirtualBox/libQtGuiVBox.so.4 ln -s /usr/lib64/qt4/libQtNetwork.so.4 /opt/VirtualBox/libQtNetworkVBox.so.4 ln -s /usr/lib64/qt4/libQtOpenGL.so.4 /opt/VirtualBox/libQtOpenGLVBox.so.4 5. Now VirtualBox uses the native GTK theme through QGtkStyle. This will probably have more uses that just QGtkStyle, I have just encountered only this though.
*** This bug has been marked as a duplicate of bug 323149 ***
Really sorry for not seeing the duplicates, I repost here because it is the only bug that mentions USE flag for this, But what exactly is wrong with the optional enabled by default "qt-static" USE flag that can also have an emerge warning about possible future problems?
I doesn't look like a duplicate to me either. Maybe a use flag might be appropriate even if it is unsupported by upstream Re-assigning to maintainers
We decided that it's a bad idea. Mixing random Qt versions is not a good idea, and if you want to do it properly use virtualbox-ose.