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Re: no constants please

This page is part of the web mail archives of SRFI 50 from before July 7th, 2015. The new archives for SRFI 50 contain all messages, not just those from before July 7th, 2015.

>>>>> "Tom" == Tom Lord <lord@xxxxxxx> writes:

Tom> If the root set is large, certainly it should be traced in several
Tom> steps, using barriers to preserve its invariants.

Is there a practical example of a system that does this?  It seems
very difficult to do, even absent an FFI to C, as your typical root
set---the current continuation---changes *all the time*.  (I'm really
curious.  I could never wrap my mind around this.)

In 1997, I developed the prototype for this FFI concurrently with
hooking RScheme's incremental collector into Scheme 48, so there's
some evidence that the FFI works with incremental collection in

Tom> Absent any further guidance from the FFI spec, I would expect some
Tom> programs to register a very large number of locations -- and worse,
Tom> locations scattered widely in memory -- using
Tom> SCHEME_GC_PROTECT_GLOBAL.  (Why wouldn't I, in a printed circuit board
Tom> CAD program, GCPROtect a field of every C structure representing an
Tom> edge in a netlist graph?)

Because of what you just said? :-)

Cheers =8-} Mike
Friede, Völkerverständigung und überhaupt blabla