Beagle SCM

GET-034: graf/GET.c base_ids/tgt_ids membership maps sized 4096 but GET_MAX_VERS=200000 → silent id drop (u8bFeed1 SNOROOM) for a file with >4096 versions

graf/GET.c builds per-side membership maps base_ids / tgt_ids with only 4096 slots, while the version cap GET_MAX_VERS is 200000. A file with more than 4096 versions overruns the map: u8bFeed1 returns SNOROOM and the id is SILENTLY DROPPED (no error surfaced), so membership is computed against an incomplete set — a correctness loss, not a crash. Spotted auditing the weave path while fixing PATCH-004; out of that ticket's scope. Method Issues.

Input

Context

• graf/GET.c sizes base_ids/tgt_ids at 4096 entries; GET_MAX_VERS = 200000. The

  two limits disagree by ~50x, so any file with >4096 versions exceeds the map.

• The overflow path is u8bFeed1(...) returning SNOROOM whose result is not gated, so

  the membership id is dropped without a trace (silent wrong answer in get/diff sizing).

• Found by the PATCH-004 worker (cherry-pick hashlet fix); flagged, not acted on, as it

  is unrelated to the cherry-pick use-after-scope.

Goals

• Membership maps cover the full version range (size to GET_MAX_VERS, or grow on

  demand) so no id is dropped for a large-history file.

• Any capacity overrun is a LOUD error (checked u8bFeed1/sFeed return), never a

  silent SNOROOM drop.

Constraints

• Native graf. ABC bounds-checking (no fixed cap that just moves the cliff). Repro-first

  (CLAUDE.md §17): a file with >4096 versions exercised through the graf GET path, asserting every membership id is present (RED today). Don't regress small-history get.

WIP

Design decisions

• (open) Localize the 4096 constant and the u8bFeed1 call site in graf/GET.c; decide

  fixed-to-GET_MAX_VERS vs a growable buffer; gate the feed return either way.

TODOs

• Repro-first: a >4096-version file through graf GET; assert membership complete (RED).
• Size/grow base_ids/tgt_ids and check the feed return (loud on overrun).

  Audit 2026-07-07 pinpoints (still live): u32bMap(base_ids, 4096)/u32bMap(tgt_ids, 4096) at graf/GET.c:327-328; the unchecked drop is (void)u32bFeed1(base_ids, WEAVE_WT_SRC) at :359 plus the collect-side feeds behind :350/:364; GET_MAX_VERS=200000 at :35 (the u32b* family, not u8bFeed1 as first filed; GET_TREE_MAX_ENTRIES 4096 at :38 is a separate limit).

• Green: large-history get/diff correct; full ctest.

Blockers and bummers

• None; self-contained. Severity is silent data/correctness loss for very large

  histories, so not urgent but should not stay latent.

Outcome

• (open) — filed 2026-06-26 from the PATCH-004 audit.