Subject: [bug#42885] [PATCH 23/27] gnu: calibre: Update to 5.13.0.

From: Leo Famulari <[email-masked]>
Date: Wed, 7 Apr 2021 23:59:22 -0400

On Wed, Apr 07, 2021 at 08:05:00PM -0400, Leo Famulari wrote:
> .sip5-real: Unable to find file "QtXml/QtXmlmod.sip"

I also noticed this passage in the QGIS ChangeLog:

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Daniel Minor <[email-masked]>   2020-07-14

    Fix FindPyQt5 cmake and python scripts

    As written, the FindPyQt5.cmake and FindPyQt5.py scripts will succeed even if
    PyQt5 is not installed. In FindPyQt5.cmake, we have PYQT5_FIND_REQUIRED rather 
    than PyQt5_FIND_REQUIRED, so the package is always treated as though it is
    optional. In FindPyQt5.py, the script will succeed with a default location for
    the sip directory, even if the PyQt5 directory is not located.

    For some systems, if enough other dependencies are installed, the build can
    get about halfway complete without the main PyQt5 dependency, and then fail
    with a message like:

    sip: Unable to find file "QtXml/QtXmlmod.sip"

    I hit this building on Ubuntu, and there have been a few similar bug reports in
    the past.
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