QT 4.6.0 with threads - UIC segmentation error

[edmondo1984]

Dear all,
I am experiencing the famous "Segmentation Error" of UIC, and I would say I have found what make it happens. I did not find how to solve it.

./configure -verbose -embedded arm -xplatform qws/linux-arm-g++ -no-qvfb -no-fontconfig -dbus -force-pkg-config -no-freetype -no-iconv -no-javascript-jit -no-script -no-scripttools -no-webkit -depths all -qt-mouse-tslib -I/usr/local/linux-arm/include -I/home/edmondo/project/sdimage/part4/usr/include/ -L/usr/local/linux-arm/lib -L/home/edmondo/project/sdimage/part4/dbuslib -prefix /usr/local/qt4arm -lpthread

This configuration does not work: when you make you get an error

/home/edmondo/project/sysapps/host/qt-everywhere-opensource-src-4.6.1/bin/uic dialogs/qprintwidget.ui -o .uic/release-shared-emb-arm/ui_qprintwidget.h
/home/edmondo/project/sysapps/host/qt-everywhere-opensource-src-4.6.1/bin/uic dialogs/qpagesetupwidget.ui -o .uic/release-shared-emb-arm/ui_qpagesetupwidget.h
make[1]: *** [.uic/release-shared-emb-arm/ui_qpagesetupwidget.h] Segmentation fault
make[1]: *** Cancellazione di `.uic/release-shared-emb-arm/ui_qpagesetupwidget.h'
make[1]: Leaving directory `/home/edmondo/project/sysapps/host/qt-everywhere-opensource-src-4.6.1/src/gui'
make: *** [sub-gui-make_default-ordered] Error 2


The same happen building with -dbus-linked

But, if you build without dbus, you do not need anymore -lpthread. And there it works!

./configure -verbose -embedded arm -xplatform qws/linux-arm-g++ -no-qvfb -no-fontconfig -fast -force-pkg-config -no-freetype -no-iconv -no-javascript-jit -no-script -no-scripttools -no-webkit -depths all -qt-mouse-tslib -I/usr/local/linux-arm/include -L/usr/local/linux-arm/lib -prefix /usr/local/qt4arm


Any idea on how to solve that? please
Regards
Edmondo

[edmondo1984]

Dear all,
I solved myself the mistery. It is very tricky and only thanks to a previous experience I wondered what was wrong.

When you configure, the compiler and the linker look for libraries in LD_LIBRARY_PATH environment variable.
Then, you call the configure passing -I and -L and you add further folders to the linking and include paths.

Well, what happened to me and the other guys who have this uic error?
The uic gets compiled against libraries in a certain folder but the includes used are not the right ones. Tipically, in one of the folders you specified with the -I option there is an header in conflict with one of the libraries. What you simply have to do is to verify that the folders you added with -I contain only the header you needs to link against the libraries you are specifying with the -L option.

The reason for the segmentation error is very simple.
Imagine you are linking against lib.so version 2. Version 2 contains for object A three methods in the header.
Imagine you then include the objecta.h in the project, but it is version 1 and only includes two methods.

What is going to happen is that, when you free or allocate an object A, this is going to have a size which is different from the expected one. This will result in a segmentation error, especially when you free the object.

In my case I was compilng and linking against dbus.
1) My -I/home/edmondo/project/sdimage/part4/usr/include/ is simply the /usr/include folders of a debian linux version for an ARM embedded device on a SD mounted on /home/edmondo/project/sdimage/part4/ .
2) I was including this folders to contains the header for the dbus library which I was linking against: -L/home/edmondo/project/sdimage/part4/dbuslib
3) the folder /home/edmondo/project/sdimage/part4/usr/include/ contains other includes! This were taken at the place of the ones of my host machine (my kubuntu laptop) but then uic was linked against the libraries of my kubuntu laptop.

How did I solve that? I copied the dbus includes in a different folder, and i -I the folders containing only the dbus includes.

Hope that can be helpful
Best Regards
Edmondo

[edmondo1984]

Anyways, that was not a matter of thread

[Rajeshsan]

Hi to all...
I need to know how to install Qt Embedded 4.6.1 for ARM compiler. Im using ARM 9 (i.MX31) Board. I need to compile phonon for board. I did like
./configure -embedded arm -nomake examples -nomake demos -phonon

I'm getting errors as
You have not explicitly asked to use pkg-config and are cross-compiling. pkg-config will not be used to automatically query cflag/lib parameters for dependencies


phonon cannot be installed due to fuctionality tests. I need to know any changes has to be made on qconfig.pri or How to compile phonon

[edmondo1984]

1) please be aware the some of the test scripts contain bugs.for example, the test for symbol visibility if you use gcc 3.3.4 does not work.
2) If you see my /configure call, you will see I excluded some packages. This is because they are already compiled for your host machine, and then of course they are not binary compatible with your ARM processor. In theory I guess you can include them by cross-compiling them and by adding them as libraries with the -L option
3) Finally, I think I can help you. but please post all the output of your /configure.

Best Regards
Edmondo

[ainu]

Also, It important in some cases, you MUST go to src/tools/bootstrap, do changes in makefile, make clean && make , and later go to src/tools/uic and re-make it, because it uses -lbootstrap WITH broken code.