Obviously not, but _threading_ primitives are not the subject of this post at all. Declared-as Non-threadsafe interfaces are. And of course one (as is happening here) one can argue whether all "system runtimes" shall be threadsafe. Right now though, they are not, and agreed/sanctioned standards don't require them to be. Again (also as happening here) opinions may differ whether changes-to-make-threadsafe would be bugfixes, enhancements, or (require) new interfaces. I have expressed my views on this. Happy to agree to disagree, though.