- wo_arena_free stamps the header: class_id = WO_CLS_FREED (0xFFFFFFFF), shard_id = 0xFFFF, flags/pad = 0
- freelist link moves from offset 0 to offset 8 so the poison survives on the list; wo_arena_alloc pops from offset 8
- wo_drop_obj aborts first on a poisoned header: a double free is a diagnostic, not a catchable state
- WO_CLS_FREED defined in wob.h beside the builtin id space
- test_arena: test_poison_on_free (poison stamped, LIFO chain through the relocated link, class drains to a fresh bump) — 17/0
- full suite SUITE_ALL_ZERO, wovm + wovm_asan rebuilt, just db-actor 10/0 (lang-41 5x marshal gate unchanged)
- story 44 status: done; board row + dependency graph L44 (41 -.follow-up.-> 44)
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
(cherry picked from commit 78ae3be403ba533db6f0e181bff201717f789a30)
- 16 tasks complete: arena, object model, borrow word, containers,
RC + budgeted cycle collector, wob_build, validating loader,
interpreter core (dual dispatch), object opcodes, drop-map unwinding,
builtins + DB_STUB + TRAP, ICALL, wovm CLI + just recipes
- 13 test suites × 2 dispatch flavors (ASan+UBSan) + CLI smoke, all green
- .wob v1 format pinned in src/wob.h + docs/plan/oop-vm/00-wob-format.md
- wo-rt.c reference event-loop preserved for sub-project 2
This is Iteration 2 of the OOP milestone; compiler front (Iteration 3)
is in progress on this branch. They meet at Iteration 4 (emitter+e2e).
