How to find out what's wrong on all of my Qt programs?

I'm using Arch Linux (Linux 3.13), when I run qtcreator, it crashes, and the same happens for other Qt based software: $ qtcreator "Qt Warning - invalid keysym: dead_actute" Segmentation fault (core dumped) $ qtalarm "Qt Warning - invalid keysym: dead_actute" Segmentation fault (core dumped) all my "qt" installed packages are: gambas3-gb-qt4 3.5.2-1 gambas3-gb-qt4-ext 3.5.2-1 gambas3-gb-qt4-opengl 3.5.2-1 gambas3-gb-qt4-webkit 3.5.2-1 kdebindings-qtruby 4.12.1-1 kdebindings-smokeqt 4.12.1-1 libdbusmenu-qt 0.9.2-2 phonon-qt4 4.7.1-1 polkit-qt 0.103.0-2 poppler-qt4 0.24.5-1 pyqt4-common 4.10.3-1 python2-pyqt4 4.10.3-1 qt4 4.8.5-7 qt5-base 5.2.0-3 qt5-declarative 5.2.0-3 qt5-graphicaleffects 5.2.0-3 qt5-imageformats 5.2.0-3 qt5-jsbackend 5.1.1-5 qt5-location 5.2.0-3 qt5-multimedia 5.2.0-3 qt5-qtsystems-git 20130509-1 qt5-quick1 5.2.0-3 qt5-quickcontrols 5.2.0-3 qt5-script 5.2.0-3 qt5-sensors 5.2.0-3 qt5-serialport 5.2.0-3 qt5-svg 5.2.0-3 qt5-tools 5.2.0-3 qt5-translations 5.2.0-3 qt5-webkit 5.2.0-3 qt5-x11extras 5.2.0-3 qt5-xmlpatterns 5.2.0-3 qtalarm 4700237.6-1 qtchooser 39-1 qtcreator 3.0.0-2 qtwebkit 2.3.3-1 telepathy-qt 0.9.3-7 How can I find out what's wrong (what the cause of the problem is) on my system?