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[SOLVED] QVector3D normalization not working in Qt Creator debug mode?



  • I'm trying to debug a C++ program in Qt Creator and I've encountered a bug that seems very odd. I initialize a QVector3D, call it foo, and after I run foo.normalize(), inspecting the variables show it's not normalized.

    Specifically, in the watch window:

    normal.x() 1.8946852...
    normal.y() 0.7071067...
    normal.z() 0.7071067...
    normal.length() 0.9999999...

    This is after a normal.normalize(). How can the length be about 1.0 when the x component is close to 2? It happens with other QVector3D names as well. Could this be memory corruption or am I missing something obvious and should just go to bed :)



  • Can you make a small compilable example that demonstrates this please? I suspect you are overwriting some memory somewhere in your application.



  • After shutting down Qt Creator, making sure my build directory was fully cleaned, and recompiling everything, it looks like the error went away. I've got Q_ASSERTs scattered through the code and nothing has hit again, so it must have been just an odd state.



  • Yeah probably a stale file in your build.


  • Moderators

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