Re: supporting DW_OP_{implicit,stack}_value

[Roland McGrath <roland at redhat dot com>]

> But it clearly depends on your preference. If you don't want to use "out
> of band signaling" then putting something, anything, in the returned
> Dwarf_Ops array is the way to go. But I actually prefer my Dwarf_Ops
> array to consist of only valid expressions. So I would use
> DW_OP_stack_value to indicate the "is a value" versus "is a location",
> but use length zero for undefined (since that is a valid expression with
> that meaning) and NULL for same_value (since it isn't expressible
> otherwise in a valid way).

I like "ou of band" for this case.  I just wanted "in-band" for the
DW_CFA_val_* cases using the DW_OP_stack_value suffix, and some way
to keep the API fairly simple.  So you suggest:

	return 0, *ops = ops_mem -> "undefined"
	return 0, *ops = NULL	 -> "same_value"

?

That could work.


Thanks,
Roland