>>Also, you can use the standard trick of decreasing the maximum single-register size and using the extra bits to identify indirect objects. That's given, you

>>Also, you can use the standard trick of decreasing the maximum single-register size and using the extra bits to identify indirect objects. That's given, you still pay the price (like mask/shift), though. That was the part the "languages like C/C#/Java have it easier" about. The point is mostly that even if built-in support (interrupts) exist in the hardware, bignums still need quite a lot of extra code in-place, plus a good optimizing/inilining compiler. Personally I am happy with constrained integer types - else the entire stack (incl. storage) must support bignums and often (like almost always) going out of range would be a bug actually.