Hey!
I think it is a popular issue. I tried the solution suggested in different websites, so far nothing works.
I am using Ubuntu 14.04 LTS, Qtcreator 4.0.3, QT 5.7.0. It happens frequently especially when editing itk codes (insight toolkit). I have i7 cpu and 16GB RAM so I think there should be no hardware issues.
Any suggestion will be appreciated!
Regards!
Ibraheem