🚀 go-pugleaf

In article <5327@batcomputer.tn.cornell.edu> braner@tcgould.tn.cornell.edu (braner) writes (amongst other things):
>I think the original question was _not_ naive:  why would one need
>a _structure_ (rather than an array) that is more than 32K in size?
>That's what many 68000 compilers cannot handle:  structure fields
>that are offset more than 32K from the beginning of the structure.
>That's because a field in a structure is accessed by adding an offset
>(a constant calculated at compile time) to the base address.  On the
>68000, the obvious, compact, efficient method is to use the indexed
>addressing mode, but that limits you to an offset of +-32K.

Maybe it is good to mention that exactly the same goes for actual
parameters and automatic variables; most compilers use a frame pointer
register (link register , typically A6) to index from. The link
instruction itself also takes a offset of +-32K. So if you can avoid it,
don't put big arrays or other variables on the stack (there's an other
danger with huge stacks: it can run into your heap).

         Leo.