>>>>> "xl" == Xavier Leroy <Xavier.Leroy@inria.fr> writes:

    xl> Ocaml performs some amount of local (intra-function) unboxing
    xl> on large integers (nativeint, int32, int64) as well as on
    xl> floats.  Version 3.00 missed some opportunities for local
    xl> unboxing of large integers, but the next release will improve
    xl> this, bringing integer unboxing to the level of float
    xl> unboxing.  However, large integers as well as floats remain
    xl> boxed across functions and inside data structures (with a few
    xl> special cases for arrays and big arrays).

You say that this doesn't happen across function-call boundaries.  Am
I right in assuming that function-call boundaries that are smoothed
away by inlining are an exception to this?

What about tail-recursion boundaries?

John.