Python Console crashes when removing non-existent vector layer

[rduivenvoorde]

Imported from Redmine: http://hub.qgis.org/issues/10755
Originally created on Mon Jun 30 02:16:22 -0700 2014, last update on Sat Nov 07 06:02:05 -0800 2015
Author: @rduivenvoorde rduivenvoorde@foo.bar (Q: should we show email?, Q: should we create @ mention?)

Description

When I try to run the following code (included in attachment crash.py) from Python Console, the QGis crashes by saying:

minidump written to C:\Users\rauni\AppData\Local\Temp\qgis-20140630-120940-6060-5464-8fdd08a.dmp (see attached minidump)

However, if I run the code (included in attachment no_crash.py), then no error occurs.

Code is following:

 iface = qgis.utils.iface

 rasterLayer = iface.addRasterLayer("crs=EPSG:4326&dpiMode=7&featureCount=10&format=image/png&layers=natura2000&styles=&url=http://geodata.nationaalgeoregister.nl/natura2000/ows", "wms master example", "wms" ) 
 vectorLayer = iface.addVectorLayer("http://geodata.nationaalgeoregister.nl/bestuurlijkegrenzen/wfs?SERVICE=WFS&VERSION=1.0.0&REQUEST=GetFeature&TYPENAME=bestuurlijkegrenzen:provincies&SRSNAME=EPSG:28992","wfs example","WFS")

 #QgsMapLayerRegistry.instance().addMapLayer(vectorLayer) #if this line is commented out, a crash occurs.

 # additional code...

 QgsMapLayerRegistry.instance().removeMapLayer(vectorLayer.id())

I am using the versions:
QGIS versioon 2.4.0-Chugiak
QGIS koodi revisjon 8fdd08a
Kompileeritud Qt-le 4.8.5
Töötab Qt-s 4.8.5
Kompileeritud GDAL/OGR-le 1.11.0
Töötab GDAL/OGR-s 1.11.0
Compiled against GEOS 3.4.2-CAPI-1.8.2
Running against GEOS 3.4.2-CAPI-1.8.2 r3921
PostgreSQL kliendi versioon 9.2.4
SpatiaLite versioon 4.1.1
QWT versioon 5.2.3
PROJ.4 Versioon 480
QScintilla2 Version 2.7.2

I am using Windows 7, if it matters.

[rduivenvoorde]

crash.py (Q: only zips are supported!)

crash.py.zip

[rduivenvoorde]

no_crash.py

no_crash.py.zip

[rduivenvoorde]

minidump added by Rauni Lillemets

qgis-20140630-120940-6060-5464-8fdd08a.zip

[rduivenvoorde]

@m-kuhn:

Crashes here only in the following order:

rasterLayer = iface.addRasterLayer("crs=EPSG:4326&dpiMode=7&featureCount=10&format=image/png&layers=natura2000&styles=&url=http://geodata.nationaalgeoregister.nl/natura2000/ows", "wms master example", "wms" ) 
vectorLayer = iface.addVectorLayer("http://geodata.nationaalgeoregister.nl/bestuurlijkegrenzen/wfs?SERVICE=WFS&VERSION=1.0.0&REQUEST=GetFeature&TYPENAME=bestuurlijkegrenzen:provincies&SRSNAME=EPSG:28992","wfs example","WFS")

QgsMapLayerRegistry.instance().removeMapLayer(vectorLayer.id())
QgsMapLayerRegistry.instance().addMapLayer(vectorLayer) #if this line is commented out, a crash occurs.
QgsMapLayerRegistry.instance().removeMapLayer(vectorLayer.id())

[rduivenvoorde]

@gioman

set/changed Category, Prio, Causes crash or corruption

[rduivenvoorde]

@jef-n

@m-kuhn wrote:

Crashes here only in the following order:

[...]

More detailed:

QgsMapLayerRegistry.addMapLayer transfers ownership of the layer
QgsMapLayerRegistry.removeMapLayer in turn destructs the layer
The python object vectorLayer doesn't notice and hence the call to vectorLayer.id() crashes (before removeMapLayer is even called a second time)

So that's a flaw in the API and a duplicate of #16 (#777.)

But crash.py doesn't use the layer after it has been removed and doesn't crash here on master.

[rduivenvoorde]

@gioman

Should we close this as duplicate?

[rduivenvoorde]

Updated by Jürgen Fischer/jef-n

Status changed from Feedback to Closed
Resolution set to duplicate

[rduivenvoorde]

Just added a label Temporary, looking what happens with that if we would clean up the labels later