Hojun-Cho
5478695922
Pre-fix the N_UN TK_AMP arm fell through silently when the operand
was an N_IDENT naming a top-level function — the let/def cascade
had no TY_FN branch, so the store at the assign site picked up
whatever AX held from prior code (commonly a stale arg register).
A subsequent (*f)(...) jumped through that junk and segfaulted.
Cstage: cmd/w6c/cgen.c N_UN TK_AMP IDENT adds a TY_FN arm before
the let/def cascade, mirror of the read-arm at line 2330 — same
mafn(opnd->str, c->cur_mod) shape. Wwstage twin in selfhost/cmd/
wcc/cgenexpr.ww cgun TK_AMP IDENT uses the analogous predicate
fnretlookup(c, nm) != nil + emitfnname(c, nm, c.curmod), matching
the cstage emit on byte-id. Both stages must land together per
rule-10 (cstage-only breaks 990-997 byte-id gates).
Combined.ww regenerated for selfhost/cmd/{w6c,wwdump}/main.combined
.ww per #110 freshness gate.
Probe: test/wcc/764_amp_fn_ident.c, 6 rows table-driven —
minimal / branched-callee / alias-chain / fn-with-args / fn-tuple
-return / cross-module. Rows 1-5 gate both stages (run + .s LEAQ
check + cs.s == ww.s byte-id); row 6 cross-module is cstage-only
because wwstage bails asserttyped on `&mod.fn` (sibling project
#184, filed). Per drew option (b) the probe exercises the address
-of without (*f)(7) — deref-call runtime coverage stays with
project #181's probe once the wwstage asserttyped bail on
N_CALL(*f) is lifted.
Phase 1 cross-mod verdict = FINE for cstage (LEAQ emits via the
already-present N_DOT TK_AMP branch at cgen.c:2477-2493); WWSTAGE
fails asserttyped on the same shape → project #184.