[PyQt] OpenGL warnings with minimal PyQt5 application

[Sibylle Koczian]

Hello,

I'm trying to use PyQt5 on a VirtualBox guest with ArchLinux installed. 
Host is Windows 7. Python version is 3.3.3. At the moment the 
application consists of this:

#!/usr/bin/env python

import sys
from PyQt5 import QtCore, QtWidgets

def main(argv):
     app = QtWidgets.QApplication(argv)
     mainwindow = QtWidgets.QMainWindow()
     mainwindow.show()
     sys.exit(app.exec_())

if __name__ == "__main__":
     main(sys.argv)

First try: 3D hardware acceleration enabled. Result of starting the 
application from a terminal:

[sib at gespenst-arch64 pyqt5]$ ./grund_1.py
OpenGL Warning: glFlushVertexArrayRangeNV not found in mesa table
OpenGL Warning: glVertexArrayRangeNV not found in mesa table
OpenGL Warning: glCombinerInputNV not found in mesa table
    [snip: lots of similar warnings]
OpenGL Warning: glSetFenceNV not found in mesa table
OpenGL Warning: glTestFenceNV not found in mesa table
OpenGL Warning: XGetVisualInfo returned 0 visuals for 0x23df2e0
OpenGL Warning: Retry with 0x8002 returned 0 visuals
    [snip: last two lines repeated two times]
OpenGL Warning: glXGetFBConfigAttrib for 0x23df2e0, failed to get 
XVisualInfo
OpenGL Warning: XGetVisualInfo returned 0 visuals for 0x23df2e0
OpenGL Warning: Retry with 0x8002 returned 0 visuals
    [snip: last three lines repeated seven times]
QXcbWindow: Unhandled client message: "_GTK_LOAD_ICONTHEMES"

The application runs and shows its empty window, as designed. But i'd 
like to get rid of the warnings.

Google and the VirtualBox documentation both tell me that the 3D 
acceleration support of VirtualBox is still experimental. Ok, I don't 
really think that I need it. Second start, 3D disabled:

[sib at gespenst-arch64 pyqt5]$ ./grund_1.py
OpenGL Warning: Failed to connect to host. Make sure 3D acceleration is 
enabled for this VM.
libGL error: failed to load driver: vboxvideo
libGL error: Try again with LIBGL_DEBUG=verbose for more details.

Application runs again. But it seems I get warnings (and even errors in 
the second case) whatever I do. This is ugly.

Same mini application using PyQt4 runs on another virtual machine (3D 
acceleration enabled, lots of warnings running glxinfo and glxgears) 
without any warning or error message. So should I return to version 4 
for Linux and use PyQt5 only on Windows?

Thank you for help!

Greetings
Sibylle