2 Commits

Author SHA1 Message Date
Brummel 76b21c00eb feat(lang): eliminate the Implicit ownership default — totality + the drop-soundness it demasks (#55)
Deletes `ParamMode::Implicit`. `ParamMode` is now `{Own, Borrow}`:
every fn-type slot on every signature carries an explicit `own` or
`borrow`, no defaulted position survives anywhere (model 0008 §2,
spec 0062). The parser rejects a bare fn-type slot; `borrow-return`
and `borrow-over-value` reject at the signature; the corpus is
migrated to minimal-ownership modes (consumed ⇒ own, read-only-heap
⇒ borrow, value ⇒ trivial-own). The documented `Implicit`-ret-mode
leak is fixed: an owned heap return now drops exactly once (live=0,
acceptance criterion 5).

This was the easy half. Removing the default ACTIVATED a family of
drop paths that `Implicit` had silently skipped — the pre-cutover
language was leaking (and in places mis-dropping) here rather than
crashing, because an Implicit scrutinee turned the drop off. Making
the modes explicit (Own) turned those paths on and exposed two
latent-bug clusters, all fixed RED-first as part of this cutover:

Drop-soundness family (four legs):
  A. lit-sub-pattern double-free — the desugar re-matched the same
     owned scrutinee in the lit fall-through; fixed by grouping
     consecutive same-ctor arms into one match (bind fields once),
     in ailang-core desugar.
  B. Cons-husk leak on non-tail arm bodies — the lit-sub-pattern
     desugar rebound the owned scrutinee via `Let $mp = xs`, which
     bumped consume_count and suppressed the existing fn-return
     partial_drop. Fixed by not rebinding a bare-Var scrutinee
     (one husk-freeing mechanism, not two).
  C. polymorphic `drop_<T>` rc_dec'd monomorphised value fields —
     the per-ADT drop fn was emitted once from the polymorphic
     TypeDef, defaulting type-var fields to ptr and rc_dec'ing
     inline Ints (segfault). Fixed with per-monomorph drop
     functions (new ailang-codegen::dropmono): the drop set is
     collected from the lowered MIR, value-type fields are skipped,
     heap fields still freed once; monomorphic-concrete ADTs keep
     their byte-identical un-suffixed drop symbol.
  D. static Str literal passed to an `(own Str)` param — the
     literal lowers to a header-less rodata constant; the callee's
     now-active rc_dec read its length field as a refcount and
     freed a static address (segfault). Fixed with the missing
     fourth StrRep::Static→Heap promotion in lower_to_mir's App arm,
     gated on Own mode (borrow args stay static, no regression).

over-strict-mode lint over-fired: it suggested `(borrow V)` for
value-typed params (which `borrow-over-value` rejects — own is the
only legal mode there) and fired on `(intrinsic)` bodies (whose
consumption the linearity walk cannot observe). Tightened to skip
both; contract 0008 updated to the narrowed firing scope.

Irreversible step — canonical-form hash reset (model 0008 §6,
acceptance criterion 6). Every signature now carries explicit modes,
so the hashable canonical JSON changed for every module. RATIFY:
the corpus-wide hash-pin reset (hash_pin, prelude_module_hash_pin,
mono_hash_stability, eq_ord_e2e, embed_export_hash_stable, the
ct4/iter*/loop_recur schema-extension pins) and the list ir_snapshot
golden were regenerated once, deliberately, as the intended one-time
consequence of removing the mode elision from the canonical form —
not a regression. Each regenerated hash verified deterministic across
two runs.

Also fixes a pre-existing latent failure surfaced by the verification
gate, unrelated to this cutover: the `every_contract_names_a_resolvable_
ratifying_test` resolver (design_index_pin) could not resolve the
" + " dual-link ratifying-test form (`uniqueness.rs + linearity.rs`)
that the #57 audit-close (dfdc65f) introduced — it shipped red on that
commit. Resolver taught the dual-link form, mirroring its sibling.

Verification: cargo test --workspace = 731 passed, 0 failed (twice,
stable); e2e 102 passed, no binary exits non-zero (corpus crash-free);
grep-clean for Implicit/fn_implicit/mode_eq across crates; every drop
fix confirmed via emitted IR + AILANG_RC_STATS balance on the head==K,
head!=K, and Nil paths. Three BLOCKEDs en route (the unsound first
husk-dec attempt, the over-strict derivation premise, the leg-B fix
direction) were each treated as a real design/spec gap and rediagnosed,
not patched over.

Supersedes #54 (return-position-only leak patch). Precondition #57
(linearity hardening) was already met. Spec docs/specs/0062, plan
docs/plans/0121.

closes #55
2026-06-02 00:03:46 +02:00
Brummel 505eb8484e fieldtest: operator-routing-eq-ord — 5 examples, 6 findings (4 working, 1 friction, 1 spec_gap)
Post-audit field test of the operator-routing-eq-ord milestone
(closed via 5170b6a + 4d45bc6). Five `.ail` Surface-form fixtures
under `examples/fieldtest/` written by an LLM-author working
strictly from the design/ ledger + public examples (no
`crates/` / `runtime/` / `bench/` reads — Iron Law honoured):

  eqord_1_fizzbuzz.ail        — FizzBuzz [1..15] via (app eq …)
                                 on Int+Str and (app gt …) on Int
  eqord_2_rational_eq.ail     — data Rational + user-instance
                                 (class prelude.Eq) by cross-mult;
                                 inner Int-eq nested in instance body
  eqord_3_newton_sqrt.ail     — Newton's method via float_lt
                                 (convergence + fabs) and float_eq
                                 (zero-guard)
  eqord_4_float_ord_must_fail.ail — (app lt 1.5 2.5) must reject
                                     at typecheck with float_lt hint
  eqord_5_float_eq_must_fail.ail  — (app eq 1.5 1.5) must reject
                                     at typecheck with float_eq hint

Findings:

  [working] x4 — primitive Eq/Ord at Int/Bool/Str/Unit;
    user-ADT Eq with nested primitive eq calls; Float named-fn
    surface (float_eq/float_lt/etc.); NoInstance Eq/Ord Float
    diagnostic with float_eq / float_lt addendum. The milestone's
    central thesis (class-dispatch is the only comparison
    surface; Float opts out via named fns) is LLM-natural —
    every (app eq …) / (app gt …) / (app float_lt …) call I
    wrote compiled on first try with no diagnostic friction.

  [spec_gap] x1 — `docs/specs/2026-05-20-operator-routing-eq-ord.md:113`
    north-star example writes bare `(class Eq)` where the
    language requires `(class prelude.Eq)`. An LLM-author who
    copies the spec verbatim hits `bare-cross-module-class-ref`.
    The milestone spec is the highest-information reference an
    LLM-author consults; the bare-vs-qualified drift mis-primes
    the pattern. Resolution: tighten-the-design-ledger — fix
    the spec example inline (separate follow-up commit). The
    existing `examples/eq_ord_user_adt.ail` already uses the
    qualified form, so the corpus is consistent; only the spec
    drifted.

  [friction] x1 — `(app compare 1.5 2.5)` at Float fires the
    same diagnostic as `(app lt …)` at Float, naming
    `float_eq / float_lt (and siblings)` as the alternative.
    But the alternatives don't return Ordering; an LLM-author
    who wanted three-way LT/EQ/GT can't satisfy that with
    float_lt + float_eq alone. The spec (lines 433-436)
    acknowledged this case in commentary — "no float_compare
    ships; build it from float_lt + float_eq if you need
    three-way" — but the diagnostic doesn't say so. Resolution:
    file as Gitea backlog issue for a follow-up tidy iteration
    (codegen-side: branch the Float-aware NoInstance addendum
    on the called method-name; the `compare` arm gets a
    one-sentence "no float_compare; build it from float_lt +
    float_eq if you need three-way" addendum).

Status: clean — no bugs, no blockers, the milestone surface is
solidly LLM-usable. Both non-working findings are tractable
forward-fixes that don't disturb the milestone's core
contracts.

Spec: docs/specs/2026-05-21-fieldtest-operator-routing-eq-ord.md
2026-05-21 01:34:19 +02:00