QGIS not compilable with Python (SIP) on Fedora 41

[Withalion]

What is the bug or the crash?

Compiling current Master on Fedora 41 finishes, but it's not able to launch QGIS with full python support.

Qt5 crash report:

Couldn't load SIP module.
Python support will be disabled.

Traceback (most recent call last):
File "", line 1, in
File "/home/Withalion/Code-Repos/Work/Lutra/QGIS-fork/build/output/python/qgis/init.py", line 85, in
import qgis.gui
File "/home/Withalion/Code-Repos/Work/Lutra/QGIS-fork/build/output/python/qgis/gui/init.py", line 25, in
from qgis._gui import *
RuntimeError: the sip module implements API v12.0 to v12.15 but the qgis._gui module requires API v12.16

Python version:
3.13.1 (main, Dec 9 2024, 00:00:00) [GCC 14.2.1 20240912 (Red Hat 14.2.1-3)]

QGIS version:
3.41.0-Master 'Master', 61b1406

Qt6 crash report:

Couldn't load SIP module.
Python support will be disabled.

Traceback (most recent call last):
File "", line 1, in
File "/home/Withalion/Code-Repos/Work/Lutra/QGIS-fork/build-qt6/output/python/qgis/init.py", line 85, in
import qgis.gui
File "/home/Withalion/Code-Repos/Work/Lutra/QGIS-fork/build-qt6/output/python/qgis/gui/init.py", line 25, in
from qgis._gui import *
RuntimeError: the sip module implements ABI v13.0 to v13.8 but the qgis._gui module requires ABI v13.9

Python version:
3.13.1 (main, Dec 9 2024, 00:00:00) [GCC 14.2.1 20240912 (Red Hat 14.2.1-3)]

QGIS version:
3.41.0-Master 'Master', 61b1406

Relevant Python packages:

Package             Version
------------------- ---------
GDAL                3.9.3
Jinja2              3.1.5
OWSLib              0.31.0
psycopg2            2.9.9
Pygments            2.18.0
PyQt-builder        1.17.0
PyQt5               5.15.10
PyQt5_sip           12.15.0
PyQt6               6.8.0
PyQt6-QScintilla    2.14.1
PyQt6_sip           13.8.0
PyQt6-WebEngine     6.8.0
PyQtWebEngine       5.15.6
PyYAML              6.0.1
QScintilla          2.14.1
sip                 6.9.0

Steps to reproduce the issue

1. Install all the system dependencies
2. Compile QGIS in clean build directory

Versions

Current master

QGIS 3.41+

Supported QGIS version

• I'm running a supported QGIS version according to the roadmap.

New profile

• I tried with a new QGIS profile

Additional context

The error says that I don't have fresh enough package, however there is no newer PyQt*_sip package available for Fedora 41. Am I just stuck until we get a newer package in fedora repository?

[lbartoletti]

@Withalion I can confirm.
According to Repology Fedora 41 have SIP 12.15.0 but, QGIS master requires SIP 12.16 available only in Rawhide

[Withalion]

I actually tried to install the newer version, which targets fedora 42, but it only brought further problems. Then the issue becomes GDAL which is currently build via numpy 1 and the newer SIP version requires GDAL build via numpy 2. I didn't know if installing newer version of GDAL would actually solve it as there is proposal to change for building via numpy 2, but the target is Fedora 42.

[troopa81]

This is well known, see here and there

IMHO, best is to wait SIP 6.10 or completely disable SIP deprecated for 6.9 ...

[t0b3]

@Withalion as a workaround on fedora 41 you may try this and report back your experience
43509f1

[Withalion]

Thanks @t0b3 for the tip! I tried to rollback on the sip package. For the Qt5 build it doesn't help at all, I still get the same error, for Qt6 build it starts with python support. The only downside is that QGIS turns to be very sluggish, it takes several seconds to open projects, even close QGIS.

[Withalion]

The slowness disappeared today, without changing anything...weird.

[troopa81]

Anyway, for now I have disabled sip deprecated with message support, so everything should be fine now