- root cause: a worker's runtime is initialised lazily on first fiber
adoption, and rt.shard_id is stamped only there — but INBOX_READY[i]
is set at thread creation. A shard that never adopts is still settled
at shutdown, carrying rt.shard_id 0 from the memset
- it then impersonated shard 0: wo_drop_obj saw 0 == 0 for anything the
primary allocated, took the "we are home" branch instead of routing,
and called class_free against rt->classes, which lazy init never
filled. &rt->classes[class_id] off a NULL base is the faulting read
- fix: stamp the runtime's real identity at thread creation. An
uninitialised shard owns nothing, so its true id makes every payload
correctly foreign and routes it to an owner that can free it
- ASan could not name this: the arena is one hand-managed malloc block,
so intra-arena reuse is invisible and it surfaces as a bare SEGV
- pinned by tests/regress/lang-41, driven from db-actor-accept. Needs
multiple shards (the corpus runner pins WO_SHARDS=1) and the ASan
build. SEGVs twice per run unfixed, clean fixed
- the HANG is a separate defect and is NOT fixed: with this in place the
harness stops losing whole sections, but idempotent-stop-2 still
fires ~1 run in 6. The story records where to look
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
(cherry picked from commit 9dca0b4b4727b976d326b29cb4c6522b62d48a73)
