[Openmcl-devel] is (pref *display* ...) supposed to work?

Gary Byers gb at clozure.com
Wed Dec 17 19:42:40 UTC 2003



On Wed, 17 Dec 2003, Timothy MOORE wrote:

>
>
> A quick question: the offset to %get-signed-long and friends is in
> bytes; how about the array length in (make-record (:array int 42))?

The MAKE-RECORD will ultimately macroexpand into something like

(#_malloc 164)		; 164 = 42 * 4

The only places where bit offsets are used explicitly are when bitfields
are involved.  (Field offsets are maintained as bit offsets internally
because that makes bitfields a lot easier to deal with.)  The "(/ N 8)" -
where N is a constant and multiple of 8 - shouldn't cause any arithmetic
to happen at runtime; I don't remember whether there's a reason that
the arithmetic isn't done inside of PREF.





More information about the Openmcl-devel mailing list