writeonce/docs
shoney.arickathil f130999018 feat(compiler): is_gc_class is inference-first (7b Phase 2a)
GC-ness now comes from the inference pass, not only the annotation. A class is
traced if the structural SCC put it in `syms.traced`, OR (temporary bridge
until demand-promotion lands) it still carries `@gc`.

- Types.symbols gains a `traced : StringSet.t`; is_gc_class reads it (union'd
  with the surviving @gc annotation). All symbols literals + both merges carry
  the field.
- typecheck_all injects the classification once (Gcinfer.classify -> traced)
  into the merged table AND every module table, before typecheck/owner/emit.
- emit.ml routes the class gc-flag and the union/drop decision through
  is_gc_class instead of the raw `.is_gc`, so structurally-inferred gc classes
  get the runtime flag. Field-kind derivation already routed through is_gc_class.
- gcinfer.traced_names exposes the traced set for injection.

Effect: docs/examples/gc-cycle now COMPILES with no annotation (the WO-E301
use-after-move at the ring-closing store is gone) — traced classes alias
freely. Bytecode is byte-identical to writing `@gc class Node`.

Verified: woc-test 566/0 (goldens unchanged — every current @gc class stays gc
via the annotation branch, and no golden has a structural-gc-non-annotated
class); oop-e2e 79/0 (gc corpus green).

Not in this slice: demand-promotion (the acyclic-aliased PriceCache case still
needs the @gc bridge) and @gc-in-source-as-error (Phase 2b); the ring RUNNING
(the RC runtime doesn't implement nullable-gcref `?Node` fields — Phase 3).
WO-W201 still fires on gc-cycle (retired in Phase 4).

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
2026-08-18 16:51:06 +02:00
..
examples feat(compiler): is_gc_class is inference-first (7b Phase 2a) 2026-08-18 16:51:06 +02:00
plan update docs 2026-08-18 02:04:58 +02:00
stories/language-runtime-database docs: iteration 14 — skillhost as a host-shaped driving workload 2026-08-16 19:53:06 +02:00
superpowers docs: implementation plan for inferred GC + mark-sweep (iteration 7b) 2026-08-18 16:33:19 +02:00
00-code-review.md docs: status board at docs/00-status.md; gap-closure spec applied; recover lost doc 2026-08-10 23:42:26 +02:00
00-principles.md docs: compiler front-end specifications and plans (Tasks 2-6) 2026-08-10 09:11:04 +02:00
00-status.md update docs 2026-08-18 02:04:58 +02:00
01-problem.md docs: remove stale old-runtime docs; abandon the ##ui frontend track 2026-08-17 20:06:36 +02:00
08-project-structure.md update docs 2026-08-18 02:04:58 +02:00