I'll link to this ticket from a call-for-testing I'm about to post on discourse -- if you happen to encounter a problem with the new non-instruction debug-info records, aka DPValues, EXPERIMENTAL_DEBUGINFO_ITERATORS or "DDD", then please open an issue and link to it here so that we can have a central point of contact.
(I imagine there's some github-equivalent to umbrella tickets in bugzilla, but I don't know what they are).