Added option for direct correction of stack pointers

The use of a pointer (not access, only for computations) after its
deallocation is forbiden in ISO C, but seems to work fine in all
platforms we are aware of. So, using that to correct stack pointers
after a stack reallocation seems safe and is much simpler than the
current implementation (first change all pointers to offsets and
then changing the offsets back to pointers). Anyway, for now that
option is disabled.
1 file changed