Arch Linux

flyingDavid

Member

Registered: 2015-02-17

Posts: 2

Install a custom QT build in parallel to the official package

Hello everyone,

(hope that's the right subforum)

I'm trying to install a custom (git based) build of QT 5.4.1 in parallel to the official Archlinux package for debugging reasons. Therefore I configured QT like this:

../configure -confirm-license -opensource \
-prefix /usr/local \
-bindir /usr/local/lib/qt/bin \
-docdir /usr/local/share/doc/qt \
-headerdir /usr/local/include/qt \
-archdatadir /usr/local/lib/qt \
-datadir /usr/local/share/qt \
-sysconfdir /etc/xdg \
-examplesdir /usr/local/share/doc/qt/examples \
-sysconfdir /etc/xdg \
-plugin-sql-{psql,mysql,sqlite,odbc,ibase} \
-system-sqlite \
-openssl-linked \
-nomake examples \
-no-rpath \
-optimized-qmake \
-dbus-linked \
-system-harfbuzz \
-journald -reduce-relocations ${SSE2} \
-developer-build \
-c++11 \
-debug \
-skip qtwebkit

which is similar to the configure command in the QT PKGBUILD.
I compiled and installed it without any problems.

After that I tried to launch kdialog using this qt build, and that's where I encountered problems.
I did the following:

export LD_LIBRARY_PATH=/usr/local/lib
export QT_PLUGIN_PATH=/usr/local/lib/qt/plugins:${QT_PLUGIN_PATH}
export QT_SELECT=5-local

$ cat /etc/xdg/qtchooser/5-local.conf 
/usr/local/lib
/usr/local/lib/qt/bin

Then I tried to launch kdialog:

$ kdialog --separate-output --checklist "Select languages:" 1 "American English" off 2  French on 3 "Oz' English" off
This application failed to start because it could not find or load the Qt platform plugin "xcb".                                                                                                                                             
                                                                                                                                                                                                                                             
Reinstalling the application may fix this problem.                                                                                                                                                                                           
Aborted (core dumped)

I don't know why the platform plugin isn't found althought I set $QT_PLUGIN_PATH, but the following fixes this problem:

export QT_QPA_PLATFORM_PLUGIN_PATH=/usr/local/lib/qt/plugins/platforms

Next try:

$ kdialog --separate-output --checklist "Select languages:" 1 "American English" off 2  French on 3 "Oz' English" off                                                  
static QPlatformTheme* QKdeTheme::createKdeTheme(): Unable to determine KDE dirs
1
3
KCrash: Application 'kdialog' crashing...
Segmentation fault (core dumped)

The style of my desktop (Plasma 5) isn't set correct as we can see at the second line. Also kdialog is crashing but that's what I'm trying to debug (looks like an segfault in qtcore). KCrash is also crashing with a segfault, which doesn't happen when I use the "normal" QT installation (the package). My conclusion is, that my build of QT hasn't replaced the QT package entirely, there is still something missing in my configuration (maybe some environmental variables).
I would like to know what I missed out, does anyone has a clue for me?

Thank you, David.