QGIS 3.14.15 **and 3.14.16-2** with GRASS won't start: Qt platform issue (Win10)

[Houska1]

Updated a functioning 3.14.1 OSGeo4W standard-release install to 3.14.15.

QGIS itself works fine (code revision d5114d2) , but QGIS-with-GRASS won't start. I get the following error:

Made me suspect a PATH issue. For some reason, C:\OSGeo4W64\bin\qgis-bin-g7.env has PATH ending with C:\Program Files\RStudio\bin and RStudio seems to install its own copy of Qt in that directory. In contrast, C:\OSGeo4W64\bin\qgis-bin.env does not have the RStudio directory added to the path. Removing that directory from qgis-bi-g7.env seems to fix the problem.

I don't know why the GRASS-enabled version would use RStudio. R itself, maybe - I do have the R provider installed. I do use RStudio for my own R work (outside QGIS), but RStudio is not in my system (i.e. at startup, QGIS not running) path variable. So it is something in the QGIS install adding it.

Prior to going digging in .env files, I reverted back to 3.14.1 and QGIS (with GRASS) started normally. I then reinstalled 3.14.15 and still had the problem, which is why I went looking (and therefore haven't checked whether that directory in in the .env path in the 3.14.1 install).

[jef-n]

See also https://trac.osgeo.org/osgeo4w/ticket/641

[gioman]

See also https://trac.osgeo.org/osgeo4w/ticket/641

So... should be close this? move it to the osgeo4w tracker?

[baswein]

Installed today sept 11 2020 and had the same problem. Looks like according to the os geo tracker it should be fixed any Idea when that will appear in osgeo?
Thanks
QGIS version
3.14.15-Pi
QGIS code revision
d5114d2
Compiled against Qt
5.11.2
Running against Qt
5.11.2
Compiled against GDAL/OGR
3.0.4
Running against GDAL/OGR
3.0.4
Compiled against GEOS
3.8.1-CAPI-1.13.3
Running against GEOS
3.8.1-CAPI-1.13.3
Compiled against SQLite
3.29.0
Running against SQLite
3.29.0
PostgreSQL Client Version
11.5
SpatiaLite Version
4.3.0
QWT Version
6.1.3
QScintilla2 Version
2.10.8
Compiled against PROJ
6.3.2
Running against PROJ
Rel. 6.3.2, May 1st, 2020
OS Version
Windows 10 (10.0)
Active python plugins
AutomaticBackup-master;
DataPlotly;
GroupStats;
Mergin;
OSMDownloader;
pickLayer;
PluginLoadTimes;
processing_r;
profiletool;
qgis-maptiler-plugin;
qgsAzimuth;
qProf;
toolbargenerator;
valuetool;
VoGisProfilTool;
workbench;
db_manager;
processing

[Houska1]

Friends, I see this has been closed. However, I just upgraded to the latest OsGeo4W install of QGIS 3.14.16-2 and rbatch 149-5, and the problem came back exactly as above. I was able to work around by manually editing out the RStudio folder in the path in the .env file and I've also commented at the (also closed) https://trac.osgeo.org/osgeo4w/ticket/641

I know it's not good form to raise bugs in multiple trackers, but when it's severe enough to make the application fail to start, and it's not fixed in the next released version, I'm raising an alarm where I can!

[Houska1]

My understanding, for the benefit of those reading about it here, is that the bug arises only in situations where the user does have RStudio installed. In this case, QGIS finds incompatible Qt components in the RStudio folder and that is why it cannot start. If the user does not have RStudio, the addition of RStudio to the PATH is harmless. This addition to the PATH is done and has been done for some time by RBatch, another part of the standard OSGeo4W install. However, it is (recent versions of) QGIS itself which then fails, due to Qt component incompatibility. So it's QGIS itself where the bug, arguably innocently caused by something else, manifests itself.

[jef-n]

Fixed in 0f2b53c

[agiudiceandrea]

Hi @jef-n, it seems the issue is not yet fixed.

As reported by an Italian user on a facebook support group, it seems that updating qgis-grass-plugin7 to version 3.14.16-3 or also installing today from scratch qgis with grass (with qgis-grass-plugin7 3.14.16-3) via the OSGeo4W network installer on a Windows 8.1 system, does not solve the issue.

The reported error is

The procedure entry point
?glyphCache@QFontEngine@@QEBAPEAVQFontEngineGlyphCache@@PEBXW4GlyphFormat@1@AEBVQTransform@@@Z
could not be located in the dynamic link library C:\OSGEO\apps\qtS\bin\Qt5OpenGL.dll.

In his system is installed RStudio.

qgis-bin-g7.env contains the following value for the PATH variable:

PATH=C:\OSGEO4~2\apps\qgis\bin;C:\OSGEO4~2\apps\grass\grass78\lib;C:\OSGEO4~2\apps\grass\grass78\bin;C:\OSGEO4~2\apps\Python37;C:\OSGEO4~2\apps\Python37\Scripts;C:\OSGEO4~2\apps\Python37;C:\OSGEO4~2\apps\Python37\Scripts;C:\OSGEO4~2\apps\qt5\bin;C:\OSGEO4~2\bin;C:\Windows\system32;C:\Windows;C:\Windows\system32\WBem;C:\Program Files\RStudio\bin

The only way to get QGIS to start was to remove ";C:\Program Files\RStudio\bin" from the end of the PATH variable string in qgis-bin-g7.env (or to move/rename the folder bin in "C:\Program Files\RStudio")

See also https://trac.osgeo.org/osgeo4w/ticket/641#comment:17 and another report to the qgis-user ml at https://lists.osgeo.org/pipermail/qgis-user/2020-September/046719.html