Re: duplicate dwarf2 reduction via comdat

[Jason Merrill <jason at redhat dot com>]

>>>>> "Ron" == Ron 603-884-2088 <brender@gemgrp.zko.dec.com> writes:

>   Question #1:  Is everyone comfortable with using linktime global symbols
> 		for references into "comdatted" information, and satisfied
> 		that a new form of operand is not needed?

I am.

> A limitation of Jason's scheme, I think, is that it results in comdatted
> information that is "promoted" to the level of a compilation unit and
> which becomes logically visible across all module scopes when in fact
> it should be visible only in some units. This limitation becomes rather
> more serious, I think, if you try to use this sort of technique to handle
> duplicate template instantiations and/or unreferenced function elimination.
> At least, I do not yet see that there is a generalization that deals with
> these additional "opportunities".

>   Question #2:  Is everyone comfortable with these limitations? Or should
> 		we formulate and consider a proposal for some kind of
> 		SUBUNIT and INCLUDE DIEs to try to eliminate the the
> 		limitations and extend the technique?

> I think I would like to see some kind of SUBUNIT and INCLUDE DIEs
> proposed.

I agree.

>   Question #3:  Is everyone comfortable with *not* including a precise and
> 		complete description in the DWARF standard of a viable
> 		hash function and candidate inclusion rules?

Yes.

Jason