Strange flickering in 64 bits

I have a quite large application with a OpenGLSurface control (practically all the window), with DoubleBuffer ON.
Application has run perfectly well for years.
When I compile it in 64 bits, it takes about ten minutes, more or less, and only some times (that’s why I say “strange”) the compiled exe flickers extensively when I move the image (dragging with the mouse). When this happens, I recompile again (no change at all) and up to now the new compilation behaves with no flickering.
So, the problem is not vital since the work around takes only a few minutes, but I’d like to know any hint or explanation about this “strange” behaviour.

If you can reproduce it in a small example project I’d submit it via Feedback. As soon as you say “64 bit” it’s probably something the Xojo team hasn’t seen yet.


The problem is, as I said, that this happens only from time to time. And I’ve not tried a small example. May be I can try it, but perhaps I compile a dozen of times and it works properly.
It is not important. Just I’m used to get the same when I compile the same, and in this case sometimes I have to compile twice because I don’t get the same.