Build error - undefined reference to symbol

[gbell12]

Under FC14:

Linking CXX executable owcrashreport
/usr/bin/ld: CMakeFiles/owcrashreport.dir/moc_QtCrashReport.o: undefined reference to symbol 'QObject::childEvent(QChildEvent*)'
/usr/bin/ld: note: 'QObject::childEvent(QChildEvent*)' is defined in DSO /usr/lib/libQtCore.so.4 so try adding it to the linker command line
/usr/lib/libQtCore.so.4: could not read symbols: Invalid operation
collect2: ld returned 1 exit status
make[2]: * [crashreport/owcrashreport] Error 1
make[1]: * [crashreport/CMakeFiles/owcrashreport.dir/all] Error 2
make: * [all] Error 2

Happy to provide whatever log files, cmake output, etc.

[laurent]

Did you see this ​https://bugs.launchpad.net/ubuntu/+source/qutecom/+bug/667159 ?

[gbell12]

I did but I'm on FC14. Didn't think it was the same problem...

[laurent]

Could you test with this patch ?

[laurent]

if it doesn't work, could you post the faulty linker command ?

[gbell12]

For some reason I couldn't get that patch to apply (-p0, -p1, -p2). Whatever. Added qt4 to a clean untar'ed 2.2.1 and same error.

Happy to post the faulty linker command. Where do I find that?

[laurent]

Replying to gbell12:

For some reason I couldn't get that patch to apply (-p0, -p1, -p2). Whatever. Added qt4 to a clean untar'ed 2.2.1 and same error.

Sorry it was made against 3.0 trunk

Happy to post the faulty linker command. Where do I find that?

make VERBOSE=1 should print full command

[gbell12]

make[2]: Entering directory `/data/home/margaret/Downloads/skype_alts/qutecom-2.
2.1/build'
Linking CXX executable owcrashreport
cd /home/margaret/Downloads/skype_alts/qutecom-2.2.1/build/crashreport && /usr/b
in/cmake -E cmake_link_script CMakeFiles/owcrashreport.dir/link.txt --verbose=1
/usr/lib/ccache/c++ -g -lpthread CMakeFiles/owcrashreport.dir/moc_FtpUpload.o

CMakeFiles/owcrashreport.dir/moc_QtCrashReport.o CMakeFiles/owcrashreport.dir/m

ain.o CMakeFiles/owcrashreport.dir/FtpUpload.o CMakeFiles/owcrashreport.dir/QtCr
ashReport.o -o owcrashreport -rdynamic -L/home/margaret/Downloads/skype_alts/qu
tecom-2.2.1/build/libs/owutil/cutil -L/home/margaret/Downloads/skype_alts/quteco
m-2.2.1/build/libs/owutil/util -L/home/margaret/Downloads/skype_alts/qutecom-2.2
.1/build/libs/owutil/thread -L/home/margaret/Downloads/skype_alts/qutecom-2.2.1/
build/libs/owutil/system -L/home/margaret/Downloads/skype_alts/qutecom-2.2.1/bui
ld/libs/qtutil -L/home/margaret/Downloads/skype_alts/qutecom-2.2.1/build/libs/ow
util/serialization -L/home/margaret/Downloads/skype_alts/qutecom-2.2.1/build/lib
s/owutil/settings -L/home/margaret/Downloads/skype_alts/qutecom-2.2.1/build/libs
/3rdparty/tinyxml ../libs/owutil/cutil/libowcutil.a -lboost_program_options -lbo
ost_serialization -lboost_signals -lboost_thread-mt -luuid ../libs/owutil/util/l
ibowutil.so ../libs/owutil/thread/libowthread.a ../libs/owutil/system/libowsyste
m.a -lcurl -lQtDBus_debug -Wl,-Bstatic -lQtUiTools_debug ../libs/qtutil/libowqtu
til.a ../libs/owutil/serialization/libowserialization.a ../libs/owutil/settings/
libowsettings.a -Wl,-Bdynamic -lQtDBus_debug -Wl,-Bstatic -lQtUiTools_debug -Wl,
-Bdynamic -lSM -lICE -lX11 -lXext -lXft -lXau -lXv ../libs/owutil/thread/libowth
read.a ../libs/owutil/serialization/libowserialization.a ../libs/owutil/util/lib
owutil.so ../libs/owutil/cutil/libowcutil.a -lboost_program_options -lboost_seri
alization -lboost_signals -lboost_thread-mt -luuid ../libs/3rdparty/tinyxml/libt
inyxml.a -Wl,-rpath,/home/margaret/Downloads/skype_alts/qutecom-2.2.1/build/libs
/owutil/util
/usr/bin/ld: CMakeFiles/owcrashreport.dir/moc_QtCrashReport.o: undefined referen
ce to symbol 'QObject::childEvent(QChildEvent*)'
/usr/bin/ld: note: 'QObject::childEvent(QChildEvent*)' is defined in DSO /usr/li
b/libQtCore.so.4 so try adding it to the linker command line
/usr/lib/libQtCore.so.4: could not read symbols: Invalid operation
collect2: ld returned 1 exit status
make[2]: * [crashreport/owcrashreport] Error 1
make[2]: Leaving directory `/data/home/margaret/Downloads/skype_alts/qutecom-2.2
.1/build'
make[1]: * [crashreport/CMakeFiles/owcrashreport.dir/all] Error 2
make[1]: Leaving directory `/data/home/margaret/Downloads/skype_alts/qutecom-2.2
.1/build'
make: * [all] Error 2

[laurent]

-lQtCore_debug is missing ...
Could you post your CMakeCache.txt ?

[gbell12]

Happy to - it's there now. Thanks for all the help.

[gbell12]

How do I get that fix? I don't see the change committed on the 2.2 repo...

[laurent]

oups i really sorry gbell12 .. i thought that this problem was solved

[laurent]

looking at CMakeCache.txt
It seems that qt4_LIBRARIES variable is not correct

qt4_LIBRARIES:INTERNAL=/usr/lib/libQtDBus_debug.so;/usr/lib/libQtUiTools_debug.a

Have you installed complete Qt4 dev package after your first QuteCom configure ...

Can you erase your current CMakeCache.txt, reconfigure and send me the new created CMakeCache.txt ?

[gbell12]

Have you installed complete Qt4 dev package after your first[[BR]]
QuteCom configure ...

Qt4 dev package has been installed the whole time.

qt4_LIBRARIES:INTERNAL=/usr/lib/libQtDBus_debug.so;/usr/lib/libQtUiTools_debug.a

Both of those files exist and are readable.

I updated the Qt4 dev packages from the RPM repos, re-cmake'd, but the CMakeCache.txt was the same...

[laurent]

Replying to gbell12:

I updated the Qt4 dev packages from the RPM repos, re-cmake'd, but the CMakeCache.txt was the same...

i really don't know why qt4_LIBRARIES variable is not correctly set ...
looking at http://trac.qutecom.org/browser/qutecom-2.2/libs/3rdparty/qt4/CMakeLists.txt
QT_QTCORE_LIBRARY_DEBUG and QT_QTGUI_LIBRARY_DEBUG should be added to qt4_LIBRARIES ...
looking at your CMakeLists.txt
QT_QTCORE_LIBRARY_DEBUG and QT_QTGUI_LIBRARY_DEBUG are not null ...

Did you erase CMakeCache.txt before cmake ?

[laurent]

Just installed a fresh fedora. I can reproduce the problem IF qt-webkit-devel is not installed ( comment:1 )
Fedora does not provide qt-webkit-devel with qt-devel package ....

Have you installed qt-webkit-devel ?

How to fix :

sudo yum install qt-webkit-devel

erase CMakeCache.txt + re-cmake

[gbell12]

It builds! So was that user error or should cmake have yelled at me?

[dneary]

Unfortunately, with different distributions packaging software like Qt in different ways, it's really hard to write CMake rules that check for everything we need everywhere. I guess this counts as a build script bug :)

[laurent]

bug fix : 700