[PyQt] PyQt 4.6 (64b) on Snow Leopard & the Symbol not found: _sipQtConnect - A longish tale

[Phil Thompson]

On Mon, 28 Sep 2009 13:23:26 -0400, Pierre Gerard-Marchant
<pierregmcode at gmail.com> wrote:
> All,
> I spent the last couple of weeks running into the same issue with PyQt  
> on Snow Leopard (10.6.1):  compilation and installation ran without  
> problems, but when I tried to import PyQt, I got the following message:
> 
> Traceback (most recent call last):
>   File "<string>", line 1, in <module>
> ImportError: dlopen(/Users/pierregm/.local/lib/python2.6/site-packages/ 
> PyQt4/QtCore.so, 2): Symbol not found: _sipQtConnect
>   Referenced from: /Users/pierregm/.local/lib/python2.6/site-packages/ 
> PyQt4/QtCore.so
>   Expected in: flat namespace
> in /Users/pierregm/.local/lib/python2.6/site-packages/PyQt4/QtCore.so
> 
> I'm using i686-apple-darwin10-gcc-4.2.1 (GCC) 4.2.1 (Apple Inc. build  
> 5646) and Python 2.6.1 (the Apple one, 64b). Because I'm using a 64b  
> Python, I wanted to Qt to run both in 32b and 64b mode. I tried  
> different Qt4 (the official 4.5.2 binaries, the official 4.5.2  
> sources) before settling on their latest 4.5 git branch (that's a  
> pre-4.5.3). These sources compiled fine with the following arguments  
> for ./configure:
> ./configure --prefix=${PREFIX} \
>             -release -opensource -shared -confirm-license \
>             -nomake examples -nomake demos -no-qt3support \
>             -cocoa -framework -arch x86 -arch x86_64 -platform macx-g+ 
> +42 \
>             -I/usr/X11R6/include -L/usr/X11R6/lib -I/usr/local/include \
>             -verbose
> When I double-check my installation, Qt seems to work with both the  
> i386 and x86_64 versions:
> 
>   lipo -info /usr/local/Cellar/qt/4.5.2/lib/QtCore.framework/Versions/ 
> 4/QtCore
> Architectures in the fat file: /usr/local/Cellar/qt/4.5.2/lib/ 
> QtCore.framework/Versions/4/QtCore are: x86_64 i386
> 
> 
> I tried 20090919 snapshots of SIP and PyQt, then the latest sources  
> (4.9 and 4.6 resp.), to no avail alas, _sipQtConnect was not to be  
> found. The corresponding configuration arguments were:
> SIP : --arch=i386 --arch=x86_64 \
>                     --bindir=${BINDIR} \
>                     --destdir=${DESTDIR} \
>                     --incdir=${INCDIR} \
>                     --sipdir=${SIPDIR}
> PyQt : --bindir=${BINDIR} \
>                     --destdir=${DESTDIR} \
>                     --confirm-license \
>                     --qsci-api \
>                     --use-arch=i386 --use-arch=x86_64 --verbose
> 
> 
> A thread from 6 months ago
> (http://www.mail-archive.com/pyqt@riverbankcomputing.com/msg16969.html 
> ) gave me the idea to double-check the content of `configure.py` in  
> PyQt-mac-gpl-4.6. In the `arch_config` function,I modified lines 908  
> and 909 from
>  >>>if a in ('i386', 'x86_64'):
>  >>>    qmake_archs.append('x86')
> to
>  >>>if a in ('i386', 'x86_64'):
>  >>>    qmake_archs.append('x86_64')
> reran python configure.py (with the same args), recompiled and bingo,  
> PyQt4.QtCore can now be imported (and now I can use the Qt4Agg backend  
> for matplotlib).
> 
> So, OK, it works, fine. But I still wonder what happened. Did I find a  
> bug ? Did I miss something ? Section 3.4 of the PyQt4 reference tells  
> that by default Qt is 32b, so PyQt4 should be compiled as 32b. But in  
> my case, Qt supports both, so I should be able to compile for the 2  
> arches, right ?

I think your workaround is correct - it will be fixed properly in tonight's
snapshot.

BTW, --use-arch should only be used at most once but it shouldn't matter
which. In fact, in your setup you don't need it at all.

Phil