Re: Rewrite of PROPOSAL 001213.1 re default location

[David B Anderson <davea at quasar dot engr dot sgi dot com>]

Dave W writes:
>Sorry, Ron, I still don't get it.  The current definition of location
>lists covers exactly this case by allowing overlapping ranges.  For
>your example, the entries should be
>
>     1       (<beginning of module>, <end of module>+1)
>                                        static address &x
>
>     2       (<first assignment>,  <second assignment>)
>                                        register Ri
>
>     3       (<second assignment>, <routine exit>)
>                                        register Rj
>
>On the phone you objected to this interpretation of the current
>spec.  What exactly do you think the above means, then?


The distinction is (I think) as follows:

Existing dwarf allows for *overlapping* ranges.
That is, if the ranges overlap, the variable exists
in two places (and, presumably is current in both?)

Ron proposes something different, 
that only a single valid locatation is in existence at one time,
and one of those is the default.


Now I'm wondering what the intent of the original was:

Did it mean literally multiple-current-addresses?
	(that makes little sense, as that would mean the
	code generator must update in multiple places)

Or did the original mean exactly what Ron proposes, but
fail to explain that there is some notion that 'only
the innermost (in the sense of
overlapping locations) location is really valid at any time'?


Ron, is this the real issue?

All: what was really intended? Is it documented and I just
missed it?

davea@sgi.com