[Qgis-developer] Building QGIS2.99 cloned from GitHub on Ubuntu 17.04 (zesty) 64-bit Python

[gordon at shieldaig.com]

The reason for the difference between `pip3 install` and `sudo apt-get 
install` of python3 packages, at least on my system, is where the 
packages are stored:

`/usr/lib/python3/dist-packages` and `/usr/lib/python35/dist-packages` 
respectively.

Not sure I understand why the difference, whether it can be easily 
managed, or even if it is a problem.  It just seemed to make a 
difference.

Rather than say people have a "messy" Ubuntu system, when it isn't, this 
information may be helpful as `python pip` and variants are widely used.

Using Qt5.7.1 sources to rebuilding QtCore.so and PyQt5, using a Qt5.7.1 
build kit, seems more possible and I will try that when I have time.  I 
am in "awe" of all the work that went into providing these shared 
modules but having to create new clean environments to build and use a 
software applications shouldn't be necessary.

I would also like to know when QGIS plans to depart from QtWebKit to 
QtWebEngine and same for Widgets.  Anyone know?

Gordon

On 2017-02-17 22:21, gordon at shieldaig.com wrote:
> Just today I made a little progress after numerous upgrades applied to
> Ubuntu 17.04.
> 
> There are several issues on my "messy" Ubuntu system  - and probably
> not on other Linux flavours.
> 
> This error seems odd, I hadn't seem it before, is there a fix?
> 
> `[ 88%] Building CXX object
> tests/src/gui/CMakeFiles/qgis_attributeformtest.dir/qrc_images.cpp.o
> /home/gordon/dev/cpp/QGIS/build-master/python/gui/sip_guipart3.cpp:2929:7:
> error: deleted function ‘virtual
> sipQgsFileDownloader::~sipQgsFileDownloader()’
> 
>        ^
> In file included from
> /home/gordon/dev/cpp/QGIS/python/gui/qgsfiledownloader.sip:33:0:
> /home/gordon/dev/cpp/QGIS/python/../src/gui/qgsfiledownloader.h:99:5:
> error: overriding non-deleted function ‘virtual
> QgsFileDownloader::~QgsFileDownloader()’
>      ~QgsFileDownloader();`
> 
> The other error, I am working on, after bringing up QGIS.
> 
> `version `Qt_5.8' not found (required by
> /usr/local/lib/python3.5/dist-packages/PyQt5/QtCore.so)`
> 
> I can install PyQt5.7.1 built using Qt5.7.1.  Hopefully that will
> work.  As it will be built with Qt5.7.1.
> 
> It has made me wonder how many "cores" were used to build pre-packaged
> libraries, anyone know?
> 
> 
> Qt5.8, is not possible for me without completely rebuilding libraries
> which are prebuilt with an out-of-date Unicode `libicu` version 57 and
> building from source has errors due to new icu version 58 not being
> picked up.  I am not attempting that.
> 
> Gordon
> 
> 
> On 2017-02-12 12:01, gordon at shieldaig.com wrote:
>> In summary, the apparent issue seems to have resulted from using `sudo
>> pip3 install PyQt5` at some point as the latest version of it depends
>> on Qt 5.7.1 while `sudo apt-get install python3-pyqt5` depends on Qt
>> 5.6.1 and the symbolic link to `libQt5Core.so.5` points to 5.6.1.
>> 
>> Simply removing and purging packages and reinstalling does not easily
>> correct this.
>> 
>> The observations regarding building using Qt 5.7.1 are still valid and
>> don't seem to affect building using Qt 5.6.1.
>> 
>> Gordon