Suddenly qt creator doesnt launch, linux

[masa4]

I dont now what i changed since last succesfull run. The full output after calling qtcreator from terminal:

qtcreator: /lib/libQt5Gui.so.5: no version information available (required by qtcreator)
qtcreator: /lib/libQt5Widgets.so.5: no version information available (required by qtcreator)
qtcreator: /lib/libQt5Network.so.5: no version information available (required by qtcreator)
qtcreator: /lib/libQt5Core.so.5: no version information available (required by qtcreator)
qtcreator: /lib/libQt5Core.so.5: no version information available (required by qtcreator)
qtcreator: /lib/libQt5Gui.so.5: no version information available (required by /usr/bin/../lib64/qtcreator/libExtensionSystem.so.4)
qtcreator: /lib/libQt5Widgets.so.5: no version information available (required by /usr/bin/../lib64/qtcreator/libExtensionSystem.so.4)
qtcreator: /lib/libQt5Core.so.5: no version information available (required by /usr/bin/../lib64/qtcreator/libExtensionSystem.so.4)
qtcreator: /lib/libQt5Core.so.5: no version information available (required by /usr/bin/../lib64/qtcreator/libExtensionSystem.so.4)
qtcreator: /lib/libQt5Core.so.5: no version information available (required by /usr/bin/../lib64/qtcreator/libAggregation.so.4)
qtcreator: /lib/libQt5Core.so.5: no version information available (required by /usr/bin/../lib64/qtcreator/libAggregation.so.4)
qtcreator: /lib/libQt5Network.so.5: no version information available (required by /usr/bin/../lib64/qtcreator/libUtils.so.4)
qtcreator: /lib/libQt5Gui.so.5: no version information available (required by /usr/bin/../lib64/qtcreator/libUtils.so.4)
qtcreator: /lib/libQt5Core.so.5: no version information available (required by /usr/bin/../lib64/qtcreator/libUtils.so.4)
qtcreator: /lib/libQt5Core.so.5: no version information available (required by /usr/bin/../lib64/qtcreator/libUtils.so.4)
qtcreator: /lib/libQt5Widgets.so.5: no version information available (required by /usr/bin/../lib64/qtcreator/libUtils.so.4)
qtcreator: /lib/libQt5Core.so.5: no version information available (required by /lib64/libQt5Concurrent.so.5)
qtcreator: /lib/libQt5Core.so.5: no version information available (required by /lib64/libQt5Concurrent.so.5)
qtcreator: /lib/libQt5Network.so.5: no version information available (required by /usr/bin/../lib64/qtcreator/../libQt5Qml.so.5)
qtcreator: /lib/libQt5Core.so.5: no version information available (required by /usr/bin/../lib64/qtcreator/../libQt5Qml.so.5)
qtcreator: /lib/libQt5Core.so.5: no version information available (required by /usr/bin/../lib64/qtcreator/../libQt5Qml.so.5)
qtcreator: /lib/libQt5Core.so.5: no version information available (required by /usr/bin/../lib64/qtcreator/../libQt5Qml.so.5)
qtcreator: relocation error: /usr/bin/../lib64/qtcreator/../libQt5Qml.so.5: symbol _ZTI26QAbstractDynamicMetaObject, version Qt_5_PRIVATE_API not defined in file libQt5Core.so.5 with link time reference

I am getting this error and qtcreator isnt opening

[jsulm]

@masa4 How did you install QtCreator?
Did you install any other Qt versions recently?
Did you do any other changes?

[masa4]

@jsulm I installed a software, after it, this issue happened i think. There were same qt libraries under /usr/lib and /usr/lib64. when i export LD_LIBRARY_PATH=/usr/lib64, problem solved. But i didnt understand how this solve the problem. I installed qt&qt creator via package manager.

[jsulm]

@masa4 Looks like another Qt version was installed (looks like 32bit) in /lib. So now, if you start QtCreator the loader finds Qt libraries in /lib which cannot be used with QtCreator as it was linked against Qt libs in /usr/lib64.