Going 64-bit is quite a bit of work: - additional 64-bit types will need additional code for type checks and conversions, switch, etc - new or improved code g

Going 64-bit is quite a bit of work: - additional 64-bit types will need additional code for type checks and conversions, switch, etc - new or improved code generator is needed (ideally, 64-bit non-pointer types should also be supported in 32-bit programs, possibly as register pairs) - new object and executable formats to handle - possibly new ABIs to support (pushing arguments onto the stack and never bothering to align the stack pointer onto a multiple of 8 or 16 boundary is kinda easy, it's pretty much free) And the above work hasn't been done.