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handoff-2 section 3.3 asks for a gate on the one scope that empties the applier's
object records while the frontend objects live on (MGPipeApplierReleaseObjectRecords,
"latent" because its only caller in the tree is MG_Test). The gate was expected green
for a CHANGED descriptor: the respecify is refused, RespecifyOnce turns the refusal
into a create plus one retry. It is not green.
MEASURED:
dropped-records probe: creates=0 applier_records=0 published=1
Nothing is emitted at all. The refusal can only reach the emitter through an answer
the row READS, and P12 made both rows answer themselves for a "confirmed" object:
the respecify is fire-and-forget (MGPipeResourceRespecifyWantsItsReply) and the
params row writes a PROVISIONAL kStatusOk (Wire_SetTextureParams). "Confirmed" is
MGPipeHandleIsPublished, which answers "did a create GO OUT" - and it stays true
after the records are dropped, which is the scope's whole definition. The only row
left that reads the real answer is create, and create is only sent when the latch is
clear - the one thing that stops being true.
So section 3.1's "clearing the latch is not enough" is the smaller half: nothing
clears the latch either, and nothing can until the applier can say "I hold nothing for
this handle" - section 3.2's third option, the reverse channel, i.e. the protocol
surface the handoff hoped to avoid paying for. That hope was priced on the trigger
being unreachable; it is still unreachable (no production caller), so the call stands,
but the cost of a production caller is now known to be the whole thing.
THE CASE IS WRITTEN AS A DEBT RATHER THAN A SPEC, and says so in its name and its
comment: it pins today's three numbers, so whoever lands the signal sees THIS case go
red and knows the repair started working. Removing the heal from RespecifyOnce would
not make it red - nothing reaches the heal - which is exactly why the assertion is on
the applier's table and the latch rather than on a count (handoff-2 section 3.3: "a
count cannot show this class of error").
Also rewritten: notes/p12/UNPUBLISH-GUARD-SIGNALS.md sections 4 and 6 now carry this
as 4.2 (sections 2 and 3 stand: neither caps generation nor FreshlyPrimed is a signal).
172/172.