Segmentation fault whe showing instrument

[Andrei Savici]

I was running Mantid version 1.29.12480 (Friday 10 Jun 2011) on RHEL6 vis ssh. I loaded a file, then clicked show instrument. I get segmentation fault. The output is pasted below. First line (QLayout ...) happens when I start MantidPlot. Loading is correct. The same file works with the latest stable release of Mantid. If I run the same thing from the terminal, I get no image of the detector banks (only axes), the same error messages, but no segmentation fault.

QLayout: Attempting to add QLayout "" to QWidget "", which already has a layout
Load-[Notice] Load started
LoadInstrument-[Warning] Trying fallback /tmp/SEQUOIA_Definition.vtp
Load-[Notice] Load successful, Duration 4.13 seconds
Object::connect: No such slot InstrumentWindowRenderTab::selectBinButtonClicked()
Vertex shader for simpleShaderProg (MainVertexShader & PositionOnlyVertexShader) failed to compile
Fragment shader for simpleShaderProg (MainFragmentShader & ShockingPinkSrcFragmentShader) failed to compile
Errors linking simple shader: "" 
Vertex shader for blitShaderProg (MainWithTexCoordsVertexShader & UntransformedPositionVertexShader) failed to compile
Fragment shader for blitShaderProg (MainFragmentShader & ImageSrcFragmentShader) failed to compile
Errors linking blit shader: "" 
Warning: "" failed to compile! 
Segmentation fault (core dumped)

[Nick Draper]

Any ideas Roman?

[Roman Tolchenov]

(In [12685]) Trying to resolve the disappearing detectors issue. re #3194

[Roman Tolchenov]

The detectors can be seen

[Martyn Gigg]

Tested with a variety of instruments and the detectors were present and there were no crashes.

I do get a message printed to the console: "Unrecognised OpenGL version", but this maybe to do with the non-standard drivers on this machine.

[Janik Zikovsky]

Unfortunately, this error is back.

I can quite reliably reproduce this error on TOPAZ and SEQUOIA at sns, through SSH only. Showing ANY instrument does this:

• The instrument window shows up and a properly rendered instrument is visible.
• A few seconds pass
• Segfault!

Vertex shader for simpleShaderProg (MainVertexShader & PositionOnlyVertexShader) failed to compile
Fragment shader for simpleShaderProg (MainFragmentShader & ShockingPinkSrcFragmentShader) failed to compile
Errors linking simple shader: "" 
Vertex shader for blitShaderProg (MainWithTexCoordsVertexShader & UntransformedPositionVertexShader) failed to compile
Fragment shader for blitShaderProg (MainFragmentShader & ImageSrcFragmentShader) failed to compile
Errors linking blit shader: "" 
Warning: "" failed to compile! 
Segmentation fault (core dumped)

This is critical as most of our analysis machines are RHEL6.

[Janik Zikovsky]

On Russell's computer (built debug), RHEL6 via SSH:

QGLShader: could not create shader 
Vertex shader for simpleShaderProg (MainVertexShader & PositionOnlyVertexShader) failed to compile
QGLShader: could not create shader 
Fragment shader for simpleShaderProg (MainFragmentShader & ShockingPinkSrcFragmentShader) failed to compile
QGLShaderProgram: could not create shader program 
Errors linking simple shader: "" 
QGLShader: could not create shader 
Vertex shader for blitShaderProg (MainWithTexCoordsVertexShader & UntransformedPositionVertexShader) failed to compile
QGLShader: could not create shader 
Fragment shader for blitShaderProg (MainFragmentShader & ImageSrcFragmentShader) failed to compile
QGLShaderProgram: could not create shader program 
Errors linking blit shader: "" 
QGLShader: could not create shader 

[Russell Taylor]

Moving this ticket up as the problem still exists. Here's what it says now for me (ssh from my rhel6 box to outback2). The text is slightly different to last time:

Vertex shader for simpleShaderProg (MainVertexShader & PositionOnlyVertexShader) failed to compile
Fragment shader for simpleShaderProg (MainFragmentShader & ShockingPinkSrcFragmentShader) failed to compile
Errors linking simple shader: "" 
Vertex shader for blitShaderProg (MainWithTexCoordsVertexShader & UntransformedPositionVertexShader) failed to compile
Fragment shader for blitShaderProg (MainFragmentShader & ImageSrcFragmentShader) failed to compile
Errors linking blit shader: "" 
Warning: "" failed to compile! 
Segmentation fault (core dumped)

[Roman Tolchenov]

Can it be a video driver problem?

[Roman Tolchenov]

Re #3194. Trying to guess what causes the problem.

The suspicion is that it is mixing openGL and QPainter.

Changeset: 984235ed67aaad0c1166bba89f6956453e5ea14f

[Russell Taylor]

Sorry, the last change didn't help but it was in the right file. Here's a stack trace:

#0  0x00000032964687cd in QGLEngineShaderManager::useCorrectShaderProg() () from /usr/lib64/libQtOpenGL.so.4
#1  0x000000329646ea32 in ?? () from /usr/lib64/libQtOpenGL.so.4
#2  0x0000003296470f65 in ?? () from /usr/lib64/libQtOpenGL.so.4
#3  0x00000032964714b3 in QGL2PaintEngineEx::drawImage(QRectF const&, QImage const&, QRectF const&, QFlags<Qt::ImageConversionFlag>) () from /usr/lib64/libQtOpenGL.so.4
#4  0x000000328dadbb37 in QPaintEngineEx::drawImage(QPointF const&, QImage const&) () from /usr/lib64/libQtGui.so.4
#5  0x000000328daedb3f in QPainter::drawImage(QPointF const&, QImage const&) () from /usr/lib64/libQtGui.so.4
#6  0x000000000080c555 in QPainter::drawImage (this=0x7fffffffc630, x=0, y=0, image=..., sx=0, sy=0, sw=-1, sh=-1, flags=...) at /usr/include/QtGui/qpainter.h:894
#7  0x0000000000a2464d in ProjectionSurface::draw (this=0x3dce000, widget=0x3b06f50, picking=false)
    at /home/tr9/Mantid/Code/Mantid/MantidPlot/src/Mantid/InstrumentWidget/ProjectionSurface.cpp:149
#8  0x0000000000a24153 in ProjectionSurface::draw (this=0x3dce000, widget=0x3b06f50)
    at /home/tr9/Mantid/Code/Mantid/MantidPlot/src/Mantid/InstrumentWidget/ProjectionSurface.cpp:89
#9  0x0000000000a14b5a in MantidGLWidget::paintEvent (this=0x3b06f50, event=0x7fffffffd0d0)
    at /home/tr9/Mantid/Code/Mantid/MantidPlot/src/Mantid/InstrumentWidget/MantidGLWidget.cpp:157
#10 0x000000328d9f565a in QWidget::event(QEvent*) () from /usr/lib64/libQtGui.so.4
#11 0x0000003296428271 in QGLWidget::event(QEvent*) () from /usr/lib64/libQtOpenGL.so.4
#12 0x000000328d9aaa0c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib64/libQtGui.so.4
#13 0x000000328d9b09db in QApplication::notify(QObject*, QEvent*) () from /usr/lib64/libQtGui.so.4
#14 0x0000000000974a1f in MantidApplication::notify (this=0x7fffffffdf40, receiver=0x3b06f50, event=0x7fffffffd0d0)
    at /home/tr9/Mantid/Code/Mantid/MantidPlot/src/Mantid/MantidApplication.cpp:24
#15 0x000000327e9579fc in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib64/libQtCore.so.4
#16 0x000000328d9fd22c in QWidgetPrivate::drawWidget(QPaintDevice*, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () from /usr/lib64/libQtGui.so.4
#17 0x000000328db9e90c in QWidgetPrivate::repaint_sys(QRegion const&) () from /usr/lib64/libQtGui.so.4
#18 0x000000328da161aa in ?? () from /usr/lib64/libQtGui.so.4
#19 0x000000328da21287 in QApplication::x11ProcessEvent(_XEvent*) () from /usr/lib64/libQtGui.so.4

[Russell Taylor]

Doing a search on some of the text that comes before the crash (comment 8) turns up quite a lot. For example: ​http://developer.qt.nokia.com/forums/viewthread/12146

Seems like it might be a Qt bug, in which case the options may well be:

(a) Hope that they fix it, or
(b) Stop using QGLWidget

[Nick Draper]

Moved at end of release 2.1

[Nick Draper]

Moved at the end of release 2.2

[Nick Draper]

moved to Release 2.4

[Russell Taylor]

I wonder if the answer to this is the new option to not use OpenGL (see #5625)? However, I can't test this as you can't get to the option to switch it off from outside the instrument window - by which time it's too late!

[Russell Taylor]

Setting MantidOptions.InstrumentView.UseOpenGL=Off does turn out to be a way to avoid this crash when starting the instrument window, though you can still cause a crash by trying to switch to the 3D view. Still, this is better than nothing.

[Nick Draper]

Moved at the code freeze for release 2.4

[Nick Draper]

Moved to r2.6 at the end of r2.5

[Nick Draper]

Moved to backlog at the code freeze for R2.6

[Nick Draper]

Bulk move to assigned at the introduction of the triage step

[Stuart Campbell]

This ticket has been transferred to github issue ​4041