All pyqt5 quick examples fails with shader program link error

[Hogne Håskjold]

$ lsb_release -rd
Description: Ubuntu 13.10
Release: 13.10

$ apt-cache policy pyqt5-doc
pyqt5-doc:
  Installed: 5.0.1-1ubuntu1
  Candidate: 5.0.1-1ubuntu1
  Version table:
 *** 5.0.1-1ubuntu1 0
        500 http://no.archive.ubuntu.com/ubuntu/ saucy/universe amd64 Packages
        100 /var/lib/dpkg/status

Graphics driver:
$ apt-cache policy nvidia-319-updates
nvidia-319-updates:
  Installed: 319.60-0ubuntu1
  Candidate: 319.60-0ubuntu1
  Version table:
 *** 319.60-0ubuntu1 0
        500 http://no.archive.ubuntu.com/ubuntu/ saucy/restricted amd64 Packages
        100 /var/lib/dpkg/status

All examples under /usr/share/doc/pyqt5-doc/examples/quick/ fails on shader compilation, example:

/usr/share/doc/pyqt5-doc/examples/quick/tutorials/extending/chapter1-basics$ python3 chapter1-basics.py
QOpenGLShaderProgram: could not create shader program
QOpenGLShader: could not create shader
QSGMaterialShader: Shader compilation failed:
""
QOpenGLShaderProgram::uniformLocation( qt_Matrix ): shader program is not linked
QOpenGLShaderProgram: could not create shader program
QOpenGLShader: could not create shader
QSGMaterialShader: Shader compilation failed:
""
QOpenGLShaderProgram::uniformLocation( matrix ): shader program is not linked
QOpenGLShaderProgram::uniformLocation( textureScale ): shader program is not linked
QOpenGLShaderProgram::uniformLocation( color ): shader program is not linked
QOpenGLShaderProgram::uniformLocation( alphaMin ): shader program is not linked
QOpenGLShaderProgram::uniformLocation( alphaMax ): shader program is not linked
QOpenGLShaderProgram::uniformLocation( fontScale ): shader program is not linked
QOpenGLShaderProgram::uniformLocation( vecDelta ): shader program is not linked
Segmentation fault (core dumped)
$

[Dmitry Shachnev (mitya57)]

This is not a bug in pyqt5. If you run some examples from qtdeclarative5-examples, you'll probably get the same errors.
It probably means that you have incomplete OpenGL drivers. Output of these commands may be helpful:

glxinfo | head
lspci | egrep 'VGA|Graphics'

[Hogne Håskjold (haskjold)]

Hi

OpenGL works fine on my system outside of pyqt5. It also works with the qtdeclarative5-examples (tested with dynamicscene.qml)

$ glxinfo | head
name of display: :0
display: :0 screen: 0
direct rendering: Yes
server glx vendor string: NVIDIA Corporation
server glx version string: 1.4
server glx extensions:
    GLX_ARB_create_context, GLX_ARB_create_context_profile,
    GLX_ARB_create_context_robustness, GLX_ARB_fbconfig_float,
    GLX_ARB_multisample, GLX_EXT_buffer_age,
    GLX_EXT_create_context_es2_profile, GLX_EXT_create_context_es_profile,
$ lspci | egrep 'VGA|Graphics'
01:00.0 VGA compatible controller: NVIDIA Corporation GF104 [GeForce GTX 460] (rev a1)
$

[Dmitry Shachnev (mitya57)]

Can you install PyQt 5.1.1 from ppa:mitya57/ppa and see if the issue is fixed there?

[Hogne Håskjold (haskjold)]

Hi

I tested with PyQt 5.1.1 from ppa:mitya57/ppa and get the same errors as before.

[Dmitry Shachnev (mitya57)]

Thanks for testing, I've now forwarded your report to upstream PyQt authors.

[Dmitry Shachnev (mitya57)]

See http://www.riverbankcomputing.com/pipermail/pyqt/2013-November/033388.html.

[Hogne Håskjold (haskjold)]

There seem to be another user on nvidia binary driver also with issues:
http://www.riverbankcomputing.com/pipermail/pyqt/2013-October/033379.html

And he got it working with nouveau driver.
http://www.riverbankcomputing.com/pipermail/pyqt/2013-November/033384.html

So the commonality might seem to be the nvidia binary driver.

[Dmitry Shachnev (mitya57)]

On Sun, Nov 17, 2013 at 4:17 PM, Phil Thompson
<email address hidden> wrote:
> I'm still stuck for suggestions. The examples are trivial. They don't even
> contain OpenGL code - the shaders causing the problems are all created
> internally by Qt.

OK. I'm reassigning the LP bug to Nvidia drivers, maybe the
maintainers have a clue.

--
Dmitry Shachnev

[Peter Würtz (pwuertz)]

I already reported this problem years ago when I tried running PyQt4 applications on OpenGl.
https://bugs.launchpad.net/ubuntu/+source/python-qt4/+bug/941826

Some Ubuntu specific modification in the nvidia driver package causes shader compilation errors in PyQt and PySide.

[John Galt (johngalt2600)]

Many years later. Same problem exists with PyQt5. I reinstall linux without installing nvidia drivers and the program works. Then I install nvidia drivers and the program crashes. On a side note. Even with out nvidia drivers installed if I run it in a su shell it crashes in a slightly different way.

[Mikhail Novosyolov (mikhailnov)]

Yes, the problem exists, I am using MAUI (mauilinux.org), Ubuntu 16.04 with Qt 5.7, I get this error only in deepin-screenshot from https://launchpad.net/~leaeasy/+archive/ubuntu/dde
I tried to rebuild the package (because it was build with another version of Qt), the rebuild was successfull, but the error resists.

Get this with both nvidia-375 and nvidia-381. When I switch to Intel Graphics on the same machine, deepin-screenshot works well,not OpenGL errors occur.

I did not have this issue beforehand with nvidia.

I will try to conact Nvidia...

[Mikhail Novosyolov (mikhailnov)]

The newer version of deepin-screenshot does not have this problem on Ubuntu 16.04, 17.04 and 17.10