In one place it says "The API provided by QAtomicInteger is guaranteed to work atomically on all processors. However, since not all processors implement support for every operation provided by QAtomicInteger, it is necessary to expose information about the processor."

On other place it says "only the 32-bit- and pointer-sized instantiations are guaranteed to work on all platforms. Support for other sizes depends on the compiler and processor architecture the code is being compiled for".

And then on other place it says:
"Since many modern architectures allow out-of-order execution and memory ordering, using the correct semantic is necessary to ensure that your application functions properly on all processors."

Thanks a lot.
Denis