Cannot build Qt SIP project on Windows: gives linkage errors (metacast,metacall,etc)

[kitekat]

I have a QWidget, written in C++. I want to create a SIP Python wrapper for it to embed it into another PyQt application.
It is possible, if PyQt is linked against the same version of Qt as embeddable widget is linked.

There is even an example on such embedding: the example (https://github.com/eyllanesc/Qt5toPyQt5)
and some talks about it (https://stackoverflow.com/questions/44258808/is-it-possible-to-embed-c-widget-to-pyqt-application).

And I have even built it under Linux without any problems, just by the manual.
And it even worked!

But for Windows it was not so easy.
I installed Qt 5.8.0. Downloaded SIP sources, built SIP, installed it with make install. Okay, SIP installed.
Then I downlaoded PyQt5 sources, built it, copied Qt DLLs into site-packages/PyQt5 -- and PyQt also started working. Okay so far...
Here is the tutorial I used to build SIP and PyQt5: https://stackoverflow.com/questions/32054021/how-to-install-sip-pyqt-on-windows-7

But when I tried to build the example from https://github.com/eyllanes/Qt5toPyQt5 , it failed.

What I did?

I did python3 configure.py -- okay, it passed, Makefiles created.

D:\Projects\Qt5toPyQt5>C:/Python35/python configure.py
QMake version 3.1
Using Qt version 5.8.0 in D:/Libs/Qt5.8.0/5.8/msvc2015_64/lib
C:\Python35\sip -t WS_WIN -t Qt_5_8_0 *-I D:\Projects\Qt5toPyQt5\sip -I C:\Python35\sip\PyQt5 -I C:\Python35\include -I D:\Projects\Qt5toPyQt5\src -c D:\Projects\Qt5toPyQt5\modules -b D:\Projects\Qt5toPyQt5\modules\PyAnalogClock.sbf -w -o D:\Projects\Qt5toPyQt5\sip\PyAnalogClock.sip

qmake -spec win32-msvc2010
Info: creating stash file D:\Projects\Qt5toPyQt5\src\.qmake.stash

But when I tried to build the Makefile with nmake (Visual Studio 2015 Pro), it crashed:

D:\Projects\Qt5toPyQt5>nmake

Microsoft (R) Program Maintenance Utility Version 14.00.23506.0
Copyright (C) Microsoft Corporation. *All rights reserved.

 * * * *cd src
 * * * *"C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\BIN\amd64\nmake.exe"

Microsoft (R) Program Maintenance Utility Version 14.00.23506.0
Copyright (C) Microsoft Corporation. *All rights reserved.

 * * * *"C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\BIN\amd64\nmake.exe" -f Makefile.Release

Microsoft (R) Program Maintenance Utility Version 14.00.23506.0
Copyright (C) Microsoft Corporation. *All rights reserved.

 * * * *cl -BxD:\Libs\Qt5.8.0\5.8\msvc2015_64\bin\qmake.exe -nologo -Zc:wchar_t -O2 -MD -GR -W3 -w34100 -w34189 -w44996 -E -Za ..\..\..\Libs\Qt5.8.0\5.8\msvc2015_64\mkspecs\features\data\dummy.cpp 2>NUL >release\moc_predefs.h
 * * * *D:\Libs\Qt5.8.0\5.8\msvc2015_64\bin\moc.exe -DUNICODE -DWIN32 -DWIN64 -DANALOGCLOCK_LIBRARY -DQT_NO_DEBUG -DQT_WIDGETS_LIB -DQT_GUI_LIB -DQT_CORE_LIB -DNDEBUG --compiler-flavor=msvc --include release/moc_predefs.h -ID:/Libs/Qt5.8.0/5.8/msvc2015_64/mkspecs/win32-msvc2010 -ID:/Projects/Qt5toPyQt5/src -ID:/Libs/Qt5.8.0/5.8/msvc2015_64/include -ID:/Libs/Qt5.8.0/5.8/msvc2015_64/include/QtWidgets -ID:/Libs/Qt5.8.0/5.8/msvc2015_64/include/QtGui -ID:/Libs/Qt5.8.0/5.8/msvc2015_64/include/QtANGLE -ID:/Libs/Qt5.8.0/5.8/msvc2015_64/include/QtCore -I"C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\INCLUDE" -I"C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\ATLMFC\INCLUDE" -I"C:\Program Files (x86)\Windows Kits\10\include\10.0.10240.0\ucrt" -I"C:\Program Files (x86)\Windows Kits\NETFXSDK\4.6.1\include\um" -I"C:\Program Files (x86)\Windows Kits\10\include\10.0.10240.0\shared" -I"C:\Program Files (x86)\Windows Kits\10\include\10.0.10240.0\um" -I"C:\Program Files (x86)\Windows Kits\10\include\10.0.10240.0\winrt" -I"C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\INCLUDE" -I"C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\ATLMFC\INCLUDE" -I"C:\Program Files (x86)\Windows Kits\10\include\10.0.10240.0\ucrt" -I"C:\Program Files (x86)\Windows Kits\NETFXSDK\4.6.1\include\um" -I"C:\Program Files (x86)\Windows Kits\10\include\10.0.10240.0\shared" -I"C:\Program Files (x86)\Windows Kits\10\include\10.0.10240.0\um" -I"C:\Program Files (x86)\Windows Kits\10\include\10.0.10240.0\winrt" analogclock.h -o release\moc_analogclock.cpp
 * * * *cl -c -nologo -Zc:wchar_t -O2 -MD -GR -W3 -w34100 -w34189 -w44996 -EHsc -DUNICODE -DWIN32 -DWIN64 -DANALOGCLOCK_LIBRARY -DQT_NO_DEBUG -DQT_WIDGETS_LIB -DQT_GUI_LIB -DQT_CORE_LIB -DNDEBUG -I. -I..\..\..\Libs\Qt5.8.0\5.8\msvc2015_64\include -I..\..\..\Libs\Qt5.8.0\5.8\msvc2015_64\include\QtWidgets -I..\..\..\Libs\Qt5.8.0\5.8\msvc2015_64\include\QtGui -I..\..\..\Libs\Qt5.8.0\5.8\msvc2015_64\include\QtANGLE -I..\..\..\Libs\Qt5.8.0\5.8\msvc2015_64\include\QtCore -Irelease -I..\..\..\Libs\Qt5.8.0\5.8\msvc2015_64\mkspecs\win32-msvc2010 -Forelease\ @C:\Users\felix\AppData\Local\Temp\nm6846.tmp
analogclock.cpp
 * * * *cl -c -nologo -Zc:wchar_t -O2 -MD -GR -W3 -w34100 -w34189 -w44996 -EHsc -DUNICODE -DWIN32 -DWIN64 -DANALOGCLOCK_LIBRARY -DQT_NO_DEBUG -DQT_WIDGETS_LIB -DQT_GUI_LIB -DQT_CORE_LIB -DNDEBUG -I. -I..\..\..\Libs\Qt5.8.0\5.8\msvc2015_64\include -I..\..\..\Libs\Qt5.8.0\5.8\msvc2015_64\include\QtWidgets -I..\..\..\Libs\Qt5.8.0\5.8\msvc2015_64\include\QtGui -I..\..\..\Libs\Qt5.8.0\5.8\msvc2015_64\include\QtANGLE -I..\..\..\Libs\Qt5.8.0\5.8\msvc2015_64\include\QtCore -Irelease -I..\..\..\Libs\Qt5.8.0\5.8\msvc2015_64\mkspecs\win32-msvc2010 -Forelease\ @C:\Users\felix\AppData\Local\Temp\nm6C2D.tmp
moc_analogclock.cpp
 * * * *lib /NOLOGO */OUT:release\analogclock.lib @C:\Users\felix\AppData\Local\Temp\nm6FE6.tmp
 * * * *cd D:\Projects\Qt5toPyQt5\modules
 * * * *"C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\BIN\amd64\nmake.exe"

Microsoft (R) Program Maintenance Utility Version 14.00.23506.0
Copyright (C) Microsoft Corporation. *All rights reserved.

 * * * *cl -c -nologo -Zm200 -Zc:wchar_t- -FS -Zc:strictStrings -D_HAS_EXCEPTIONS=0 -O2 -MD -W3 -w34100 -w34189 -w44996 -w44456 -w44457 -w44458 -wd4577 -DNDEBUG -DAnalogClock_LIBRARY -DQT_CORE_LIB -DQT_GUI_LIB -DQT_WIDGETS_LIB -DUNICODE -DWIN32 -I. -ID:\Projects\Qt5toPyQt5\src -ID:\Libs\Qt5.8.0\5.8\msvc2015_64\include -ID:\Libs\Qt5.8.0\5.8\msvc2015_64\include\QtCore -ID:\Libs\Qt5.8.0\5.8\msvc2015_64\include\QtGui -ID:\Libs\Qt5.8.0\5.8\msvc2015_64\include\QtWidgets -IC:\Python35\include -Fo @C:\Users\felix\AppData\Local\Temp\nm7032.tmp
sipPyAnalogClockcmodule.cpp
sipPyAnalogClockAnalogClock.cpp
Generating Code...
 * * * *link /NOLOGO /DYNAMICBASE /NXCOMPAT /DLL /MANIFEST /MANIFESTFILE:PyAnalogClock.pyd.manifest /SUBSYSTEM:WINDOWS /INCREMENTAL:NO /OUT:PyAnalogClock.pyd @C:\Users\felix\AppData\Local\Temp\nm7957.tmp
 * Creating library PyAnalogClock.lib and object PyAnalogClock.exp
sipPyAnalogClockAnalogClock.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: virtual struct QMetaObject const * __cdecl AnalogClock::metaObject(void)const " (__imp_?metaObject@AnalogClock@@UEBAPEBUQMetaObject@@XZ) referenced in function "public: virtual struct QMetaObject const * __cdecl sipAnalogClock::metaObject(void)const " (?metaObject@sipAnalogClock@@UEBAPEBUQMetaObject@@XZ)
sipPyAnalogClockAnalogClock.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: virtual void * __cdecl AnalogClock::qt_metacast(char const *)" (__imp_?qt_metacast@AnalogClock@@UEAAPEAXPEBD@Z) referenced in function "public: virtual void * __cdecl sipAnalogClock::qt_metacast(char const *)" (?qt_metacast@sipAnalogClock@@UEAAPEAXPEBD@Z)
sipPyAnalogClockAnalogClock.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: virtual int __cdecl AnalogClock::qt_metacall(enum QMetaObject::Call,int,void * *)" (__imp_?qt_metacall@AnalogClock@@UEAAHW4Call@QMetaObject@@HPEAPEAX@Z) referenced in function "public: virtual int __cdecl sipAnalogClock::qt_metacall(enum QMetaObject::Call,int,void * *)" (?qt_metacall@sipAnalogClock@@UEAAHW4Call@QMetaObject@@HPEAPEAX@Z)
sipPyAnalogClockAnalogClock.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: __cdecl AnalogClock::AnalogClock(class QWidget *)" (__imp_??0AnalogClock@@QEAA@PEAVQWidget@@@Z) referenced in function init_type_AnalogClock
sipPyAnalogClockAnalogClock.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) protected: virtual void __cdecl AnalogClock::paintEven
```t(class QPaintEvent *)" (__imp_?paintEvent@AnalogClock@@MEAAXPEAVQPaintEvent@@@Z) referenced in function meth_AnalogClock_paintEvent
sipPyAnalogClockAnalogClock.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: static struct QMetaObject const AnalogClock::staticMetaObject" (__imp_?staticMetaObject@AnalogClock@@2UQMetaObject@@B) referenced in function "void __cdecl `dynamic initializer for 'plugin_AnalogClock''(void)" (??__Eplugin_AnalogClock@@YAXXZ)
PyAnalogClock.pyd : fatal error LNK1120: 6 unresolved externals
NMAKE : fatal error U1077: '"C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\BIN\amd64\link.EXE"' : return code '0x460'
Stop.
NMAKE : fatal error U1077: '"C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\BIN\amd64\nmake.exe"' : return code '0x2'
Stop.

Can I somehow cope with it?

[koahnig]

@kitekat said in Cannot build Qt SIP project on Windows: gives linkage errors (metacast,metacall,etc):

D:\Projects\Qt5toPyQt5>C:/Python35/python configure.py
QMake version 3.1
Using Qt version 5.8.0 in D:/Libs/Qt5.8.0/5.8/msvc2015_64/lib
C:\Python35\sip -t WS_WIN -t Qt_5_8_0 *-I D:\Projects\Qt5toPyQt5\sip -I C:\Python35\sip\PyQt5 -I C:\Python35\include -I D:\Projects\Qt5toPyQt5\src -c D:\Projects\Qt5toPyQt5\modules -b D:\Projects\Qt5toPyQt5\modules\PyAnalogClock.sbf -w -o D:\Projects\Qt5toPyQt5\sip\PyAnalogClock.sip

qmake -spec win32-msvc2010
Info: creating stash file D:\Projects\Qt5toPyQt5\src\.qmake.stash

There is a mixture of msvc 2010 and msvc 2015. In general msvc versions are not compatible with each other with the exception of very recent versions. My guess is your switch use of msvc 2010 is creating the problem. Try to use all with the same version of msvc and do not mix. At least you have removed one ambiguity in the process.

[kitekat]

Replaced "2010" with "2015" in configure.py

Nothing changed, the same errors apper.

[koahnig]

@kitekat

Are you mixing 32 and 64 bit versions?

My msvc experience is really a long time back. At the moment I doubt I can help you here.

[SGaist]

Hi,

Are you properly exporting your class ?

[kitekat]

@SGaist

Well, i don't know...
I've just started with SIP...

[SGaist]

I'm asking about your C++ class.

[kitekat]

Well, yes. There was not set q_decl_export, don't know why.
When I set it manually, it started building and working.

[SGaist]

Because it's not something mandatory and it's Windows specific. In any case, it's usually a good thing to have when writing libraries.