Hi, while there was a little section about what breaks with QT on [1] it didn't mention that the threading model was changed completely without any compatibility layer, and QT4 uses this old threading model in their network/ssl layer - or at least they provide and set the locking callbacks.
So unless openssl upstream (or someone else knowledgeable) gives an clear indication how to replace the old threading model with the new one, I'd rather not touch this part of the code. I'll see, however, whether I can provide a patch for the other compile errors. best, Gert [1] https://wiki.openssl.org/index.php/1.1_API_Changes
