Re: integer overflow

[Richard Stallman]

    There are many cases where it's important to read an integer from some
    other program, so it's important to be able to read integers larger the
    Elisp's largest fixnum (tho less so for integers larger than the
    host system's natural "int").
    Examples are file sizes, process ids, user ids, ...

Would it make sense to set up a variable to control this?
You could bind it to t for those special cases.