integer sizes

[Doug Gwyn <gwyn>]

You failed to show the #define for "uint60" on e.g. a VAX.
How are you going to port your code to a 32-bit machine?

By implementing your very-long-integer data types in a way
that does not exceed the guaranteed minimum limits of any
ANSI C conforming implementation, you would significantly
improve the portability of your code.  There are well-known
techniques for implementing extended-precision arithmetic
(e.g. Knuth Vol. 2); having such routines in the standard
library could be useful but forcing the compiler to handle
this issue directly is counter to the general flavor of C.

If you really want non-portable code (e.g., for reasons of
speed), you can still do that too, but there is no reason
the C language should be made considerably more elaborate
just so you can code in terms of "uint60".