Install old version PyQt4 on a mac by compiling the source

[Phil Thompson]

On 10/07/2021 11:16, Felix Voigt wrote:
>> On 9. Jul 2021, at 10:09, Phil Thompson <phil at riverbankcomputing.com> 
>> wrote:
>> 
>> On 08/07/2021 19:37, Felix Voigt wrote:
>>> Hello everyone,
>>> today I tried the same with PyQt5 with the following results.
>>> The configure process succeeded:
>>> cd ~/documents/tmp/PyQt5-5.15.4
>>> ~/.pyenv/versions/2.7.18/bin/python2.7 configure.py --qmake
>>> /usr/local/Cellar/qt at 5/5.15.2/bin/qmake
>>> --sip=/Users/felixvoigt/.pyenv/versions/2.7.18/bin/sip --verbose
>>> The make process failed:
>>> make
>>> -> In file included from
>>> /Users/felixvoigt/documents/tmp/PyQt5-5.15.4/sip/QtCore/qsocketnotifier.sip:26:
>>> /usr/local/Cellar/qt at 5/5.15.2/lib/QtCore.framework/Headers/qsocketnotifier.h:117:35:
>>> error: constexpr function never produces a constant
>>>      expression [-Winvalid-constexpr]
>>>    Q_DECL_CONSTEXPR_NOT_WIN bool isValid() const noexcept { return
>>> *this != QSocketDescriptor(); }
>>>                                  ^
>>> /usr/local/Cellar/qt at 5/5.15.2/lib/QtCore.framework/Headers/qsocketnotifier.h:117:75:
>>> note: undefined function 'operator!=' cannot be used
>>>      in a constant expression
>>>    Q_DECL_CONSTEXPR_NOT_WIN bool isValid() const noexcept { return
>>> *this != QSocketDescriptor(); }
>>>                                                                       
>>>    ^
>>> /usr/local/Cellar/qt at 5/5.15.2/lib/QtCore.framework/Headers/qsocketnotifier.h:124:42:
>>> note: declared here
>>>    friend Q_DECL_CONSTEXPR_NOT_WIN bool operator!=(QSocketDescriptor 
>>> lhs,
>>> 1 error generated.
>>> Any ideas how to fix it?
>>> Kind regards
>>> feli_x
>> 
>> As the error is referring to Qt source code and not SIP generated code 
>> then the problem may be your version of Xcode.
>> 
>> Phil
> 
> 
> Hello Phil and thanks,
> 
> meanwhile I updated my xcode from beta 9.0 to 11.3.1.
> I managed to configure pyqt5 via:
> ~/.pyenv/versions/2.7.18/bin/python2.7 configure.py --qmake
> /usr/local/Cellar/qt at 5/5.15.2/bin/qmake
> --sip=/Users/felixvoigt/.pyenv/versions/2.7.18/bin/sip —verbose
> 
> Although there was a warning, which I neglected:
> Project WARNING: Qt requires at least version 10.14 of the platform
> SDK, you're building against version 10.13. Please upgrade.
> 
> The make process succeeded, there were also many warnings, which are
> too many to store them I thought.
> 
> Finally:
> make install
> 
> Now, my next problem is, if I start the python program, the line "from
> PyQt5 import QtCore, QtGui” gives an error message:
> ~/.pyenv/versions/2.7.18/bin/python2.7 test.py
> Traceback (most recent call last):
>  File "test.py", line 1, in <module>
>    from PyQt5 import QtCore, QtGui
> ImportError: No module named sip
> 
> I tried including the folder
> /Users/felixvoigt/.pyenv/versions/2.7.18/bin in my PATH, which was not
> a solution.
> 
> Does somebody know how to configure sip correctly such that it can be
> found by pyqt5?

https://www.riverbankcomputing.com/static/Docs/PyQt5/installation.html#building-the-sip-module

Phil