Qt World Summit: Register Today!

Application crash - possible graphic issue

  • Hi,
    we have several customers who installed our QML app (Qt 5.7.0 MSVC2013) and from the description of the problem we received from customers it seems the app crashes during startup when it loads and tries to display qml file. On 98 % of PCs our app runs without the issue.

    I remember that on some PCs we had issues with opengl/angle. On one particual PC the app ran only when Qt::AA_UseDesktopOpenGL was set, on another Qt::AA_UseOpenGLES must have been set.

    We set no attribute in our app.

    Do you have some tips on how to diagnose and fix the issue?

  • Lifetime Qt Champion


    One thing I would do is compare the graphic stack between the computer where your app crashes and those where not. Especially the driver version used on them.

  • If you have a customer that can reproduce it, get a crash log from them. You should be able to get the crash line from that and start looking into it from there.

    If you build for windows with MSVC you can always generate the .map file with your build and save that off. Then you can determine what line of your code the crash was on from their crash log (with no lines/function info). Another option is to leave debugging symbols in and get a full backtrace.

    If you are working with a posix compiler like clang or g++, then just don't strip the exe and build with -g. That should give you plenty of info to work with.

    The AA_UseDesktopOpenGL flag will cause Qt to use the system libgl.so (or the windows equivalent, sorry not a windows guy). This can definitely cause problems since that can be a different version than you're code or Qt is expecting. Could cause crashes or other graphical bugs. Forcing it to AA_UseOpenGLES would be a good first step in debugging the problem as well.

Log in to reply