Qt widget setParent

[wysota]

Because you are lucky and the order in which the compiler deletes objects that goes out of scope is exactly the one that is needed to avoid a crash. I don't want to inspect your code right now, so I'll give an easy example:

#include <QObject>
int main(int argc, char **argv){
  QObject o1;
  QObject o2;
  o2.setParent(&o1);
  return 0;
}

#include <QObject>
int main(int argc, char **argv){
  QObject o1;
  QObject o2;
  o2.setParent(&o1);
  return 0;
}

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Run this application and see if it crashes. Then switch lines 3. and 4. and run it again and again see if it crashes.