glBufferData(target, 0, NULL, usage) DEFINES its store - that is not the
orphaning idiom - so HasDefinedContent is set, and MappedData() answers a
non-null pointer for it because the shadow reserves one byte whatever the size
(PipeResource.h:140-143). Reading MappedData() alone therefore put the call on
the split arm's respecify(nullptr)-plus-follow-up shape, whose walk emits
nothing for a zero-length range (ResourceTracker.h:253), and the
InitialBytesNotCarried self-check aborted by name on the first such call in the
bsl-esc-menu trace.
The predicate is 'HasDefinedContent && GetSize() > 0': there are bytes here,
not merely a defined store. The split arm's own condition is untouched - moving
it instead would send the zero-byte case to the UncarriedInitialBytes refusal
in the wire escape.
PipeFill.cpp.
One resource_subdata record's blob is staged whole in SEG_STAGE, so a range
larger than that arena is Fatal{RingOverrun, SEG_STAGE} at the encoder rather
than a split: the CI traces abort there on a 128 MiB arena's whole-buffer
follow-up against a 32 MiB segment.
- ClientSession::StageCapacityBytes(), the twin of EventRingCapacityBytes, so
the emitter can size against the arena the codec allocates from.
- MGPipeStageChunkBytes(): clamp(segment/4, 4096, segment), 0 when there is
nothing to fit (monolith, the server role's own uploads, no session).
- PipeFill.cpp's two buffer content walks take that cap instead of the
record's own 2^32-1 bound, so an over-long range becomes several contiguous
ascending records. StagedShadowStore::Adopt already accumulates coverage.
ClientSession.h/.cpp, GpuWritePending.h/.cpp, PipeFill.cpp.
The remove-artifact-clutter jobs deleted trace fixtures and results while
reading job/artifact inventories through unchecked process substitution, so
a failed GitHub API page looked like 'no failed cases' and fixtures for a
red retrace could be deleted. test.yml cleanup also did not wait for the
retrace-split lane even though those jobs download the same fixtures.
Read both paginated inventories into files before any deletion so an API
failure fails the step, add retrace-split to the cleanup dependencies, and
retain fixtures plus result artifacts for failed cases in all three lanes.
swung0x48