Comment by layer8
The problem is when C calls expect to be on a particular thread. Either the main event thread, in a GUI context, or the same thread as some related previous call.
The problem is when C calls expect to be on a particular thread. Either the main event thread, in a GUI context, or the same thread as some related previous call.
The problem is that C expects to have enough stack to put stuff there, but green threads allocate small stacks to reduce (virtual) memory use.