Brummel
2ad58ada17
Second iteration of spec 0064. Closes false-positive class 1: applying
a local function-typed binder (a HOF predicate param like
std_list.filter's `p`) treats its args as Consume because
callee_arg_modes resolves only globals -- so a heap arg reused after
(app p h) false-fires use-after-consume.
Fix: BinderState gains fn_param_modes: Option<Vec<ParamMode>>, seeded
at all three function-typed binder introduction sites -- params and
lam-params from the signature (param_tys), let-binders from the
LetBinderTypes table built in iter 1 -- via a new fn_modes_of helper
(strip_forall + Type::Fn { param_modes }). callee_arg_modes reads a
local Var callee's fn_param_modes before falling back to globals; the
existing App arg-walk maps Borrow to a borrow walk unchanged.
Scope call (orchestrator): all three seeding sites, not just the param
path that unblocks filter -- the point of this hardening cycle is to
leave no latent class (the #57-from-0063-deferral lesson), and the
extraction is the same at each site with the table already built.
Two tasks, RED-first: Task 1 adds examples/c1_local_hof.ail to the
harden list (RED: use-after-consume on filter_box's h); Task 2 adds the
field + seeding + callee_arg_modes read (GREEN), plus two in-source
unit tests (param path via signature, let path via hand-built table)
and a borrow-predicate test helper. Diagnostic-only; no schema/type
change. plan-recon mapped current post-iter-1 line numbers; parse gate
fired on the inlined fixture (RED confirmed).
refs #57