I just found that a pointer to this function is null. Means that if you will use interpreterProxy->getStackPointer() in plugin, you will crash VM.
Could it be that it declared twice in sqVirtualMachine.c ?
... sqInt getStackPointer(void); /* Newsqueak FFI */ void *startOfAlienData(sqInt); usqInt sizeOfAlienData(sqInt); sqInt signalNoResume(sqInt);
#if VM_PROXY_MINOR > 8 sqInt getStackPointer(void); /* Alien FFI */ ...
(at least this code looks suspicious)
and why at assignment point it does conversions? VM->getStackPointer = (sqInt *(*)(void))getStackPointer;
while rest of functions don't require them?
In header it declared as: sqInt *(*getStackPointer)(void);
NBInterpreterProxy majorVersion 1 NBInterpreterProxy minorVersion 12
(means that it should be there :)