check_file resolved typedecl bodies in file order with an eager
under->size copy, so any body referencing a typedecl declared LATER
read its size-0 placeholder and baked it in: alias size 0, tagged-
union maxsz 0 (the F0 m5_match $48-frame under-allocated box), struct
field offsets collapsed, array element stride 0 — a whole cstage-only
family (7 size()-probe rows, all cs-fail/ww-pass pre-fix). wwstage's
demand-driven tinfofornode was order-independent on every row, so this
aligns cstage UP to the measured runtime-correct side (the #263-era
ruling; rule 10's align-down governs acceptance surface, not layout
correctness). Oracle: ken /tmp/ken_62_oracle.md — union size is 8B tag
+ roundup8(max CHASED member size), a fixed point over the module,
never a function of decl order.
resolve_typename now resolves a referenced-but-unresolved typedecl on
demand via resolve_typedecl (cycle-guarded by Type.resolving); the
pass-1.5 loop funnels through the same helper. No consumer can see an
unresolved placeholder by construction.
CYCLE GUARD — #69 ABSORBED into this rider (rob's rider condition):
true typedecl cycles now LOUD-reject on BOTH stages — "circular type
dependency" — mirroring harec's in_progress check (ref/harec/src/
check.c:4767 "Circular dependency for '%s'"). Pre-guard: cs silently
sized cycles 0; wwstage HUNG on an alias cycle (`type a = b; type
b = a` — ken's hang probe /tmp/ken62/c1_cycle.ww, killed at the 20s
timeout) and stack-overflowed on a struct value cycle. The check sits
at the VALUE-position size consumers only (alias root, struct field,
array elem, tuple member, union member), so the legal pointer
self-ref (`type node = struct { next: *node }`, the io.stream shape)
stays accepted, byte-id. wwstage gets the twin tinfo.resolving flag
(lib/ww/typ.ww) + circularnamed in check.ww; its arm loud-STOPS
(os.exit) rather than accumulating — wwstage's AST-level alias
walkers (resolvealias, aliaslookup chains) follow TNAME->TNAME by
name, blind to the tinfo table, and spin on a cyclic alias graph even
after the table edge is cut to tyerr (measured); cstage accumulates,
its single-peel ternaries cannot loop.
TWO-LAYER SPLIT — this is ONE bug number (#62) deliberately split
across THREE commits (this rider + F1 + F2), per ken's sizes-correct ≠
payload-correct proof: in NORMAL decl order both stages size the box
correctly (16/24, frames $64) yet both still run exit 2 — the box
STORE is word0-only, a chase-blind copy-WIDTH lookup in cgen, NOT the
type table. EXPECTED-FAIL after this commit: m5b_match1/m5_match stay
exit-2 both stages (now byte-id BOTH orders; pre-fix the fwd order was
$48-frame divergent). The Layer-2 sites and destinations:
- F1 (cstage): cg_widen_tagged_store single NAMED peel,
cmd/w6c/cgen.c ~2464 — the type_chase_named census family.
- F2 (wwstage): rhsstructpayload bare name-keyed structlookup, no
alias chase, selfhost/cmd/wcc/cgenutil.ww:3062 (structlookupchain
:1691 already exists).
Banked runtime payload-readback rows for F1/F2: /tmp/impl62r_layer2_rows.md.
Test 944_alias_decl_order_size_run: every size class pinned in BOTH
decl orders (sizes, named union, struct field offsets, array elem,
2-level chain — norm + fwd twins, prefix-luck-breaking last-word
readbacks), 3 cycle BUILDERR rows + the legal ptr-self-ref row,
(void|base) no-regress control; dual-stage + per-row byte-id (arrelem
rows byte-id exempt: pre-existing #60 index-over-alias divergence,
order-independent, cited at the rows). lib/ww/typ.ww is an embedded
source: both main.combined.ww regen'd + committed (freshness gate).
For an annotation-less `let p = pt{...}` checkletassign planted exprtype's
N_STRUCTLIT result — the struct decl's BODY node (N_TSTRUCT, per #66) — as
the let's type. Every cgen local-arm dispatch (cgdot read, cgassign
tagged-field store, the alias peel) is N_TNAME-keyed, so the body matched
no arm: field reads fell to the module-qualified fallback and emitted the
FIELD NAME as a global symbol (MOVQ f(SB) — link-fail, #211 name-leak
family; silent corruption if a same-named global exists), and a tagged-
field assign fell to the assign-resolver TY_TAGGED loud bound. Both PG5
wwstage symptoms, one root; plain structs leaked too. Normalizing the
inferred binding to the synthesized TNAME (mktname + tinfofornode stamp)
routes every consumer down the already-byte-id annotated path. cstage
needs no twin: check.c:1477 clet carries Sym.type (tinfo) and its
emission is annotation-invariant (probed). Test 811: 10 rows x 2 drivers
+ 10 asm-byte-id; pre-fix wwstage link-fails every unannotated row
(incl. the `...` autofill and parenthesized forms; nested s.f.g ran
but cs!=ww asm).
slot = roundup8(size(elem)) — 8B is a FLOOR, not a ceiling (user-
ratified 2026-06-04; the #237 fieldslotsize precedent; (str,str)=48B
predates this — tagged was the one truncated >8B kind). Pre-fix the
checkers truncated a tagged element to one 8B slot and every cgen
transport walk strode wide=(STR||SLICE)-else-8: cstage read the
NEIGHBOR slot, wwstage read ZEROS — both-wrong-differently, so the
byte-id gates were blind (prober-9 PG1, /tmp/p9).
One stride accessor per stage — tuple_eslot (cgen.c) / tupeslot
(cgenstmt.ww) — now feeds every tuple walk; the per-site predicates
are deleted as absorbed. Sizer: check.c N_TTUPLE + check.ww
tupleelemslot gain the TY_TAGGED arm (astsize already rides the type
table since commit 0). Routes flipped to the accessor, both stages
symmetric: cursor producers (lit/slot-to-cursor; tagged ident
elements load their box from the slot — cgexpr's tagged ident load
is word0-only), let-receive (tuple_store/tupstore generalized to
eslot/8 words), N_RETURN send, by-value param receive, arg
restage/drain (tagged stays loud per C-t2), destructure
(MLET/MASSIGN, ident + sret + in-cap), t.N read + len(t.N) +
global-g.N offset walks (t.N gains the tagged box load: AX=tag,
DX/CX/R8=payload — the is/as spill cursor), sret classifier, DATA
emit. wwstage cgtagvariantidx gains the #67 stamped-carrier arm
(flatvariantidxt on .type_) — its AST-only key silently clamped
't.0 is size' to tag 0; fused here because the tuple-element read
this commit wires is its only exercisable consumer.
Exit invariant: zero silent tagged-tuple paths — in-cap shapes
(<=4 GP eightbytes) are correct end-to-end; everything else is LOUD:
over-cap sret return (#22b, task #28), call-arg (C-t2 #32),
non-local literal element sources (#22b/#23), tuple-in-union payload
(#242/#22b), global static-init, element write (pre-existing).
Closure proof-grep at HEAD: 'tuple_ebytes|tupebytes' -> 0 hits;
'wide.*=.*(TY_SLICE|TY_STR)' tuple-walk survivors are all behind
tagged loud-guards (cgen.c:2535/2568/12013 widen-store + over-cap
send; cgenutil.ww:3527 twin).
Latent cross-checks closed by the accessor: wwstage MLET-sret strode
esz (4 for i32) vs cstage 8; wwstage param-receive strode slotsize
(composite slotsize) vs cstage 8; both now the accessor's floor-8.
Tagged inits in pins use the CAST form (5: size) — the bare
untyped-int widen-store mis-tag is pre-existing at master and filed
(task #33).
941 gains 13 rows: t22_* size/align folds (+ void-elem 0-slot pin),
the full runtime round-trip (read, is/as, both element orders, void
variant, destructure, literal-let), two-tagged-elem in-cap and
float+tagged in BOTH orders (ken k1/k2 regression-pinned as rows),
t.N-as-call-arg, 5 loud pins (arg, over-cap return, call-source
element, global init, element write), and the sret_narrow_mix_*
triple below. Runtime rows exit-checked under both drivers +
byte-id. 129/129; unit tests green; sizelint clean.
ken R1 (re-validation fix): an OVER-CAP tuple init whose rhs is not a
CALL fell past every cstage N_LET store arm to NOTHING — silent
uninitialized-frame reads — while wwstage loud-rejected the same
shape. Pre-existing for (str,str) literals; the #22a tagged slots
routed >16B-box tagged shapes into it (k5b/k5c/k5d, base-correct
because base truncated them in-cap). cstage now routes the rhs
through cgexpr (the cursor materialisers carry the exact wwstage
loud texts) with a trailing fatal as the net; 941 pins both the
tagged and the (str,str) spellings of the hole.
reviewer-22 (review fixes, folded): the MLET-receive slot flip above
landed ALONE on the wwstage over-cap sret family — the ww RETURN-send
and MASSIGN-receive still strode packed esz (4 for u32), so
`let (a,b,c) = f()` over (str,u32,str) read c at slot offset 32 while
ww's send wrote it packed at 28: a ww runtime REGRESSION vs base
(base was packed-consistent on both sides — ran right, byte-diff).
Both walks now stride the slot (send mirrors cstage's
`wide ? esz : 8`; MASSIGN strides tupeslotn) — closing, in the same
stroke, the pre-existing base skews: ww `let t = f()` over-cap
narrow-mix read (reader slot-laid vs send packed, runtime-wrong at
base) and the cs≠ww asm on all three routings. Second find: t.N
tagged element as a CALL ARG — cstage rides its generic
node_istaggedarg cursor push, but wwstage's kind-gated aistagged
missed N_DOT and mis-routed the box into the widening branch
(taggedvariantindex -1 clamped to 0: callee read variant 0, silent,
ww-only). cgenutil.ww gains the N_DOT arm (aistagged + pushargsrev),
the #67 stamped-carrier twin of the N_INDEX (#12) arm. The N_DOT arm
was a LIVE wwstage stdlib miscompile: hextest's import graph carried
two t.N tagged-arg sites (base .s diff = exactly the clamped-tag
PUSHQ pair) — the 989 lib-byteid ratchet caught the convergence and
#59.4 graduates to M_ID (runtime-correct per 979_hex_run). Probes:
/tmp/r22. Residual filed: tagged arg from deref/cast/unwrap sources
is a word0-only read on BOTH stages (pre-existing, base-confirmed) —
generalizing wwstage's kind gate to cstage's type-keyed check rides
that task.
The wwstage size()/align() fold walks the AST (astsize), and its
N_TTUPLE arm still summed PACKED element sizes — C-t0 flipped the
checker type table (tupleelemslot) and cstage's N_TTUPLE to the
ratified slot layout but missed this second wwstage sizer.
size((u32,u32)) folded to 16 on cstage and 8 on wwstage: a silent
cs≠ww in every folded tuple-size constant, plus the recursive
escapes (a tuple inside struct/array size computation under the
fold). Runtime-confirmed at 74767c7.
astsize N_TTUPLE now reads the tuple tinfo, making tupleelemslot
the single wwstage tuple sizer; the tagged-element slot fix (#22
22a) lands in that one place next. 941 gains c0_sizefold_slot +
c0_sizefold_recursive rows (exit-checked under both drivers +
byte-id).
Hare's delete also takes a slicing place (harec check.c:1981-2027
EXPR_SLICE; Hare spells it delete(xs[i..j])): remove [lo, hi) — shift
[hi..len) down count = hi-lo strides, len -= count, cap unchanged; lo
defaults 0, hi defaults len, so delete(xs[:]) clears the slice with
storage retained. Checker accepts N_SLICE next to N_INDEX (object must
chase to a slice, harec :2024); the old range-unimplemented reject and
its #35 cite drop.
Lowering (both stages, converged byte-identical by construction) is the
single-element arm's same-slice whole-stride word-copy loop with a
DYNAMIC src offset (count*esz via a src register) instead of the
constant one-stride. Base shapes: local slice ident, deref-of-local,
plus NEW indexed local-slice base xs[g][lo:hi] — the fold-5a consumer
shape (regex.ha:333 delete(jump_idxs[group_level][..]); outer stride
off the type table). Bounds stay implicit, inheriting the documented
single-element posture (no index checks anywhere in cgen). Operands
evaluate left-to-right, exactly once, before the shift (harec order);
only the header ADDRESS is taken before operand eval, so a bound
expression's writes through the slice land before the copy.
test/809: 64 fixtures — full/explicit/re-clear/head/mid/tail/empty
a:a/end-boundary len:len/explicit 0:0 on a never-appended (nil-ptr)
slice, single-vs-range equivalence, cap preservation, esz 1/2/4/8/16/24
copy tails against the dynamic src, operand order-of-eval (lo/hi CALLs
fire once each, in order) + aliasing-visibility pins, the EXACT
[][]size regex consumer shape, deref base, 2 reject rows w/ diagnostic
text; every accept row cs==ww asm byte-id. test/804: reject_range row
retired (form now accepted), reject_nonindex text follows the widened
message.
An array literal with more elements than the declared [N] passed the
per-element accept-if-fits checks in both stages and cgen then stored
every element at its natural offset, writing past the slot: local
frames smashed silently (the repeat form [1,2,3...] into [2]int wrote
at the saved BP), module DATA corrupted neighbours. All four
declaration contexts (local let, module let, def, struct-field
literal) funnel through one choke point per stage — arrlit_init_fits
(check.c) / checkarrlitfits (check.ww) — which now pre-counts the
literal (skipping the ... marker) and rejects count > N naming both
counts.
cstage clet's blanket has_arr_repeat bypass is narrowed to non-array
declared targets: repeat literals into arrays now run the same
overlong + #130 range checks wwstage's checkletassign always ran
(the bypass let [2]u8 = [999...] dodge the range check cstage-only).
checkarrlitfits also recurses into NESTED array-literal elements
(declared elem node N_TARRAY): cstage catches the nested shape
through its typed-literal assignability net, which wwstage's untyped
elements have no analog of — [2][2]int = [[1,2,3],[4,5]] at module
scope silently emitted corrupted DATA (1,2,4,5) and the struct-field
twin likewise. Recursion through the one choke point closes any
depth; a named-alias element type still bypasses — task #16.
alen==0/nil-length stays exempt ([0]/[_] sentinel conflation and
un-inferred [_] in def/struct-field — task #11); a non-INTLIT length
child (def-named [N]) is exempt in wwstage — task #13; under-long
literals keep their current accept (Hare rejects — task #10);
wwstage's overlong accept at assign/call-arg/return position (cstage
already rejects) is task #12; exact-fit bare-int nested cs-reject/
ww-accept divergence is pre-existing — task #17.
wwstage had no EXPR_ASSERT-family intercept: the checker left bare
assert/abort calls untyped (asserttyped gate 4 skipped them by design)
and cgcall fell through to the regular call path, emitting
CALL assert(SB) for a symbol that exists nowhere — link-fail. cstage
was already correct (tag ty_err at check.c:1536-1572, lower inline via
rt_abort at cgen.c:6618-6663).
Mirror the same tag-then-lower pair: exprtype N_CALL stamps the call
void and the callee TY_ERR behind the scopelookupprefer no-shadow gate
(the isassertfam predicate), with the cstage arg diagnostics (cond must
be bool, msg must be str, arity caps); cgcall keys on the TY_ERR tag
and emits the identical CMPQ/JNE/rt_abort sequence. A user-shadowed
assert/abort (same-module or cross-module, the #45 shape, task #14)
stays untagged on the regular call path — byte-id for all existing lib
code preserved.
The cond check does NOT alias-peel: cstage compares ty_bool by
identity (check.c:1560), so `type myb = bool` is rejected there;
wwstage aligns down per rule 10 (a resolvealias here was accepting it
— cs/ww accept-reject divergence). Widening both stages together
belongs to the alias-peel choke-point arc (task #5, #47/#68).
The resolvewalk N_IDENT resolution counter learns the builtin shape:
an unshadowed abort/assert ident binds no sym BY DESIGN, so wwdump
-r's zero-unresolved gate (990 probe 4) counts it resolved instead of
failing builtin-using units.
test 957: 13 rows — pass/fail/msg/bare abort (run exit + rt_abort
stderr content; no-msg rows pin EMPTY stderr = the (NULL,0) shape),
assert in an imported module, same-module + cross-module shadow
controls, 5 checker rejects pinned on diagnostic CONTENT (shared
substring; cstage prefixes pos, wwstage cerr is bare) incl. the
alias-of-bool cond row pinning the rule-10 down-alignment; each
positive row pins cstage run exit + cs==ww byte-id. On pre-fix master
11/13 rows trip (survivors = the two shadow controls).
Residual (separate root, deferred diagnostic class): zero-arg assert()
is not intercepted by either stage; cstage rejects via the generic
undefined-ident path, wwstage's undefined-callee diagnostic is the
class deferred behind wiring checkfile into w6c_ww.
Indexing through a pointer-to-array auto-derefs, so esz and the element
classification must come from the pointee array's ELEMENT (cstage
idx_eff semantics, cgen.c:1163). Two halves of one root class:
A (wwstage-only, cs!=ww, cstage runtime-correct): elemsizeofc's #270-2
nested-array block treated an N_TPTR pointee-array like a [N][M]T outer
index and returned the whole-array size — every p[i] read/write/
compound scaled by N*size(T), and the same wrong element belief reached
the store-width chooser (var-idx write emitted an N*8B aggregate copy
sourced at the 8B rhs slot: caller-frame smash, the siphash round()
corruption). Fixed via two wwstage choke-points mirroring idx_eff:
idxeffti (tinfo: NAMED peel + TY_PTR->TY_ARRAY drill; feeds elemsizeofc
and elemissignedc/elemisfloatc/elemisf32c) and idxelemtn (node: element
tnode with the same drill; feeds every cgindex/cgassign/nodeisstr/
match-scrutinee elemtn resolution).
B (BOTH stages identically wrong, byte-id-BLIND): the TK_AMP &base[i]
arm read bu->sub->size without the ptr peel (&p[3]-&a[0] = 96, not 24).
cstage now routes esz through idx_eff.
A and B are FUSED by the pre-existing routing topology, not by choice
(rule 11): wwstage's TK_AMP arm already reads its esz via elemsizeofc
(selfhost/cmd/wcc/cgenexpr.ww:4095, the #11 addr-of twin of the #10
cgindex fix), so fixing A's choke-point flips wwstage's half of B in
the same stroke. A standalone A leaves &p[i] transiently cs!=ww;
B-first is the mirror transient; carving the TK_AMP caller out of the
fixed choke-point to preserve the wrong stride for one commit would be
a deliberate known-wrong intermediate (rule-7, vetoed by rob). One
choke-point, two enrolled routes — un-fusable without a red
intermediate.
Close-by-construction proof-grep (both stages): every remaining raw
sub->size index-stride read is TY_ARRAY-gated, a slice-only builtin
(delete/insert), a checker-stamped element tinfo (indexresult already
decays *[N]T, check.ww:2277-2284), or a non-index context (tuple
slots, let-init elements). Two true residuals filed with site+symptom
instead of silently absorbed: N_SLICE through *[N]T does not decay
(LOUD type error, Hare divergence; team task #18) and non-ident
cast-expression index bases keep wwstage's 8B-default esz (pre-existing
#74-style cluster; team task #19). cstage's N_INDEX read-side
str/slice header gates also move from u->sub to esub (identical for
every non-ptr-to-array base; honest for *[N]str — pre-fix BOTH stages
were runtime-wrong there, differently).
949_ptrarr_index_run pins the class at runtime + byte-id: {1,2,4,8}B
elems, const+var idx, param/local/cast bases, read/write/compound,
neighbor guards, &p[i] pointer-difference, siphash-round mix shape.
989_lib_byteid: siphash_test graduates #59.7 DIVERGE -> ID (ratchet
tripped loud pre-update; no other #59.x pin flipped in the same run).
(*p)[i] (sub-bug C) follows separately.
The checker computed TY_TUPLE size as the packed element-size sum
((u32,u32) = 8B) while every cgen cursor-transport site strode 8B
slots (16B). 16B tuples were blind to the split (slot == packed);
packed tuples hit it everywhere: cstage let-receive keyed on sz 16/32
missed sz 8 and dropped word 1, the cgfn param receive spilled
8B/element into a packed-sized local (saved-BP clobber, SIGSEGV), and
mixed (u32,f64)/(u32,str) shapes missed the receive arms entirely.
Slot layout is now the SSoT (user-ratified): the flip lives in the two
checkers' N_TTUPLE size computation only (check.c, check.ww
tupleelemslot + stamp); cgen's packed-keyed walks (t.N read, #235 len
arm, over-cap sret send/receive pair) align onto the slot stride, and
the wwstage t.N read gains the natural-width load (tnodeloadop) to
byte-id with cstage's fldloadop. ttupleelem.offset re-stamped
slot-cumulative (no consumers yet). The #242/#243 eightbyte-share
loud-stop dissolves by construction (no two narrows ever share an
eightbyte) — 940's eightbyte_share row graduates to a runtime
round-trip. Hare-layout divergence documented at both checker sites;
re-alignment is task #60. #32 send skew and #33 wwstage literal-let
receive are separate commits on this base.
941_tuple_slot_layout_run pins the matrix: 4 packed rows fail at the
parent (8/21 checks), 3 neutral anchors prove 16B/32B emission
untouched.
Hare's insert(xs[idx], v) (ref/harec/src/check.c:745
check_expr_append_insert — append/insert share the checker arm,
"insert" at :786): checker accepts an INDEX place over a slice plus
one value, stamps void; idx == len is a legal end-insert (the
ref/hare os/exec/platform_cmd.ha:86 idiom). Loud-rejects with exact
texts: spread form insert(xs[i], vs...) (filed, #35 — also covers
harec's with-length form via the arity check), range place (not
Hare; harec only parses ACCESS_INDEX, :784), non-index operands,
array bases, wrong arity. delete()-parity throughout.
Lowering (both stages, converged byte-identical by construction) is
a DESUGAR: append(xs, v) — reusing append's grow (rt_ensure) and the
entire #34 value-store dispatch (scalar / str-slice header / tagged
widen / struct fill) verbatim, one boxing choke-point — lands v at
slot len-1; then a rotate-right of [idx, len) moves it home through
a fresh per-site esz frame scratch (@insscr). The rotate is delete's
shift loop in reverse (descending j, the safe memmove-up direction)
and is a same-slice whole-stride raw byte move — no boxing exists
for any element kind. idx evaluates BEFORE the grow (Hare's
left-to-right operand order — pinned by the pregrow_len_idx row,
insert(xs[len(xs)-1], v): pre-grow [7,13,11] vs post-grow [7,11,13];
an idx==len(xs) end-insert cannot discriminate, the rotate
degenerates either way). Base shapes: local slice ident (LEAQ) and
deref-of-local ptr-to-slice (MOVQ); others rule-7 loud-stop, like
delete.
test/807: 57 fixtures — front/middle/end + idx==len via len(xs) +
the pre-grow eval-order pin, esz 1/2/4/8/16/24/56 (MOVB/MOVW/MOVL
tails, struct body, str header, 7-qword tagged from a typed local
[the regex fold-3 ha:347 newinst shape] and from a cast rvalue
[ha:419/441]), empty-slice grow, (*p)[i] deref base, front-insert
loop, 6 checker reject rows with diagnostic-text checks; every
accept row cs==ww asm byte-id.
F5 (task #7): the N_LET aggregate-copy arm's source-addr enumeration
(cgen.c #265/#268) had TY_ARRAY-ident/N_DOT/N_INDEX bases but no
TY_SLICE base and no deref-spine shapes, so `let e: th = xs[0]` fell
out with havesrc=0 — cstage emitted NOTHING (slot uninitialised),
wwstage fell to its scalar default (8B truncation): gate-blind cs≠ww
(p6min13). Every remaining ADDRESSABLE rhs now resolves through
cgplaceaddr (the C1 resolver; enumerated arms dispatch first, their
asm untouched), and the arm closes by construction with a loud tail —
nothing below it can initialise a >8B struct/array slot, so any
unhandled rhs shape dies loud instead of silently. A pre-tail #38b
guard keeps the established `?`/`!`-on-sret loud-stop marker in
wwstage (mirror of cstage's pre-arm fatal; pre-fix that shape reached
the cgtryunw/cgtryprop gates which the tail now pre-empts in let
position).
Reviewer-C2 inheritance: `let c: capture = (*ts)[i].cap` (aggregate
leaf behind a deref spine) — wwstage's documented cgdot aggregate-leaf
loud is retired for let position (cglet routes the copy through the
resolver before cgexpr sees the leaf; the loud stays as the guard for
non-let expr positions), and cstage's silent no-copy on the same shape
is fixed by the same resolver fallback.
By-value RANGE payloads ride the same class: N_FORRANGE's single-bind
load truncated every aggregate element to one fldloadop word. Both
stages now word-copy the full element extent (MOVQ run + sized
MOVL/MOVW/MOVB tail, the #270-1b idiom) for esz > 8. wwstage esz is
re-keyed elemsizeof→elemsizeofc (the 8-sentinel hid struct elements
from the copy gate — the #8 named-narrow precedent), with a
stamped-slc.type_ fallback + element-tnode synthesis for non-ident
scrutinees (tinfo SSoT, #209/#211). The wwstage checker now binds the
ELEMENT type on single-bind ranges via a synthetic N_LET binder node
(mirror of cstage check.c N_FORRANGE scope_define(..., elem, ...));
pre-fix the binding's decl was the N_FORRANGE node itself, so any
field read off a by-value binding asserttyped-bailed. The checker
half folds in under rule 11 because the split is unsound in either
order: cgen-first is untestable (every field read off the binding
still bails), checker-first converts that loud bail into the 8B
SILENT truncation — only the pair closes the class.
FC0 graduates: regex.finish's by-value range over 24B charset elems
(non-ident scrutinee re.charsets) was the lib/regex byte-cmp's ONLY
hunk since fold-1 — cstage 8-of-24-byte copy + IMULQ $24 vs wwstage
1-byte MOVZBQ, runtime-masked by the no-op loop body. The byte-cmp is
now ZERO hunks (regex_test.combined.ww, w6c vs w6c_ww).
#36 disposition: NOT folded. p6min9/p6min10's remaining failure is the
struct-ident field rhs inside a struct LITERAL (cg_structlit_fill
under-copy) — a different choke-point from the let-copy source-addr
machinery; they still exit 4 here and stay blocked on #36 (read half
landed in C2).
Residual filed as task #43: an UNANNOTATED aggregate let
(`let e = xs[0]`) still skips the wwstage arm (aggn/letslotsize are
annotation-keyed; cstage keys the stamped n->type and now full-copies)
— cs≠ww on that shape remains, #38-family. A landmine comment in
test 805 marks the gap.
test 805: +6 rows — let-from-slice-elem 16B (p6min13 verbatim) /
24B/40B/12B(MOVQ+MOVL tail) matrix / deref-spine leaf / by-value range
([]struct both-fields sum, []capture 40B, []str 24B header) / range
edges (empty slice, by-VALUE binder-mutation pin, 12B elem MOVL tail)
/ reject row pinning the loud-tail text on both stages. All six fail
at the pristine parent 403625e (re-verified post-rebase; 121 prior
fixtures stay green there).
? and ! assume ONE success member end-to-end: the checker collapses
the result to the first non-error variant (check.c tagged_success_type
/ check.ww exprtype) and cgen emits a single tag compare, so any other
success member is silently mistaken for an error — ? propagates it to
the caller (p11h: []capture read back as nomem, exit 21), ! aborts on
it. Until the honest subset-union result typing lands (task #14, harec
check.c:2759-2835), both stages loud-reject |success| > 1 at the
checker choke-points (one per stage), identical diagnostic, both ops
per rob's one-class ruling (#133 precedent). (T|err1|err2) — one
success, many errors — stays legal (925 canary + new accept rows).
F9 rides along (task #12): wwstage scruttype only resolves IDENT/DOT,
so the direct forms f()? is T / match(f()?) / f()! is T slipped its
lenient-miss contract and were silently ACCEPTED where cstage rejects
(cs!=ww, gate-blind). checkisas/checkmatchexhaust now resolve the
try-result via exprtype, keyed on the RESOLVED success type — a named
tagged success ((ab|nomem)? is i32) keeps being accepted, matching
cstage's verdict empirically.
test/wcc/806: 11 rows x dual driver + byte-id accepts (26 fixtures);
reject rows pin exact per-stage diagnostic text; p11h + q_card2_unw
graduated to rejects; call-arg-position reject + void-success accept
pin position-independence and the dominant lib/ (void|err)? shape.
Tasks #5 + #12; #14 lifts both gates together.
Hare's delete(xs[i]) (ref/harec/src/check.c:1981-2027): checker accepts
an N_INDEX over a slice-typed base, stamps void; loud-rejects the range
form delete(xs[i..j]) (stays filed on #35 — regex fold-2b's consumers
are all single-element), non-index operands, array bases, wrong arity.
Lowering (both stages, converged byte-identical by construction):
ascending word-copy loop shifts [i+1..len) down one esz stride, then
hdr.len -= 1; cap unchanged. The move is a same-type whole-stride byte
copy — src and dst are elements of the SAME slice, so no boxing exists
for any element kind; one loop serves scalar/narrow/str/struct/tagged.
esz off the STAMPED base type (#34/#48 discipline). Base shapes: local
slice ident (LEAQ) and deref-of-local ptr-to-slice (MOVQ — the fold-2b
delete_thread shape); others rule-7 loud-stop.
test/804: 38 fixtures — first/middle/last/to-empty, esz 1/4/8/24/56
(MOVB/MOVL tails + 7-qword tagged), cap-unchanged, (*threads)[i], 4
checker reject rows; every accept row cs==ww asm byte-id.
A one-step `let xs: []T = [e0,e1,..]` had two faults. #31 (silent, cs!=ww):
the #258 array→slice borrow wrapped the un-addressable N_ARRLIT directly as
the N_SLICE base and cgen never spilled it to a stack slot, so .ptr dangled
(`let xs:[]i32=[10,20,30]; xs[1]` returned the un-stored header 1; []u8/[]str
segfaulted). #25 (over-strict): a slice target fell through to the exact-
element type_eq borrow gate, rejecting bare-int-width ([]u8=[1,2,3]) and str
elements the array-init path coerces.
Fix (re-stamp + per-borrow scratch; both stages byte-identical asm):
- Checker re-stamps the slice arrlit as [count]T, reusing the array-init
per-element coercion + range-check (#25): in-range accepts, out-of-range
loud-rejects. cstage arrlit_init_fits gains a TY_SLICE arm; wwstage
checkletassign mirrors it and stashes the synthesized [count]T tnode on
arrlit.lhs (free for N_ARRLIT) so cgen can size the backing NODE-wise
(elemsizeofc) and count from the tnode's .rhs intlit — the arrlit's own
value tinfo carries the literal's untyped element (unsized), so node-first
sizing is required (a cstage/wwstage representation divergence; cstage's
Type IS sized and reads base->type).
- cgen materialises the N_ARRLIT borrow base into a FRESH per-borrow
@slicescr stack slot (distinct slot per borrow: a borrow's backing must
outlive the lowering, so it can't share a cached @aggargscr/@tagscr-style
slot — two live borrows would alias one backing; localalloc/local_alloc
is always-fresh), filled by REUSING the array-init element fill extracted
from the N_LET path (cstage cg_arrlit_fill_bp, wwstage cgarrlitfillbp —
same store sequence the byte-id-green `let a:[N]T=[..]` uses, the
frame-order + store-op guarantee), then LEAQ'd as the base.
Supported ONLY at a `let` init. In call-arg / return / assign position
there is no addressable backing, so both stages LOUD-REJECT ("bind it to a
`let` first") — aligning cstage DOWN to wwstage (which already refused the
untyped arrlit element) per rule-10; this closes#31's silent call-arg
segfault as a compile error. Full non-let support is deferred (#33).
Escape (rule-8 WHY): a `let xs:[]T=[..]; return xs;` returns a slice into a
freed frame slot = dangling, IDENTICAL to the pre-existing named-array
borrow and Hare-consistent (no escape analysis / GC / heap promotion).
Test 953_arrlit_slice_run: 8 accept rows (cstage runtime readback +
cs==ww byte-id, frame-size canary incl.) covering the #31 i32 pin, bare-int→u8
coercion, str readback, the multi-live soundness pin (xs[0]+ys[0]=5, not 8 —
proves fresh-per-borrow), and a mutate-through-borrow proof; 4 reject rows
(out-of-range element + the three non-let contexts, loud in both stages).
Tuple-element slices stay blocked by the pre-existing #30 array-init FATAL.
wwstage over-rejected an inline `let g: []pt = [pt{..}, pt{..}]`. The
N_ARRLIT exprtype arm inferred its element type from the first element,
an N_STRUCTLIT, whose exprtype arm deliberately returns the struct BODY
(N_TSTRUCT) per #66. The array->slice isassignable arm then typeeqast's
the declared element (N_TNAME "pt") against that body and bails on the
TNAME-vs-TSTRUCT kind mismatch -> confident-false -> reject. The reject
is a KIND mismatch, not a nominal-compare weakness: typeeqast is already
streq-keyed for N_TNAME.
Narrow fix: when the first arrlit element is a named struct literal,
capture the NAMED type (mktname) so su.lhs matches the declared N_TNAME
shape, mirroring cstage's element inference. typeeqast and the
N_STRUCTLIT #66 body-return are untouched; non-named elements keep the
existing first-element shape. e.type_ via tinfofornode still resolves
[N]pt for cgen, so cstage/wwstage stay byte-identical.
Test 687 gains struct_pt (sum+len+cap == 14), struct_3f (mixed-width
u8/i64/i32 field offsets == 23), and struct_arrvar_local (the
array-VARIABLE form still accepts+runs; local scope since the
module-scope variable form is the deferred #22 link gap).
The #258 borrow desugar lowers `let s: []T = arr` to a runtime
`arr[0:len]` (N_SLICE over the array base) so the slice header is built
at run time. That is only meaningful for a LOCAL let — a fn body
executes the borrow. A module-level let is static data with no runtime
to run the borrow; its rhs must stay the raw N_ARRLIT so cgen can
materialize it as DATA.
cstage splits this by checker: clet (the desugar site, check.c:1993)
runs only from cstmt (local statements); module-level lets are checked
in check_file pass-2 (check.c:2549) which never desugars. wwstage runs
ONE checkletassign for both — function-body lets via resolvewalk's
post-order walk (a block scope is pushed, c.cur != c.top) and top-level
lets via checkfile pass-2 (no scope pushed, c.cur == c.top). Mirror
cstage's split by gating the desugar call on `c.cur != c.top` (the same
module-scope test as check.ww:184). The #130 module-level assignability
check in checkletassign is untouched.
Without this, a module-level `let g: []u8 = [1u8,2u8,3u8]` reached cgen
as N_SLICE in wwstage but N_ARRLIT in cstage — the cs!=ww shape that
blocked #10 part-a's wwstage data-emission. Locals stay byte-identical
(named-array->slice still works, exit 8 both stages); selfhost combined
.ww regenerated.
`[_]T = [...]` (canonical Hare array-length inference) silently
miscompiled to a zero-length array: the parser already left the array
type's length child nil as the infer sentinel — distinct from an
explicit [N] — but neither checker stamped the real count, so `len(x)`
returned 0 with no diagnostic (rule-7 silent miscompile). Module-level
was worse on wwstage, where `x.len` on ANY global array (even an
explicit [N]) fell to the SB fallback and mis-emitted `MOVQ len(SB), AX`
(linker: undefined reference to len).
The length lives in the stamped TYPE and cgen already keys stride /
length / data-emission off it, so stamping the inferred count at the one
checker inference point closes it permanently (rob's #7 ruling):
- check.c clet + module-level N_LET pass-2: count the initializer's
elements and patch the array type's length (the Sym too, so a later
x.len reads the inferred alen). No-init / non-array init can't infer
-> loud error, never a silent zero-length array.
- check.ww inferarraylen: the wwstage twin — stamp a synthesized
N_INTLIT length child before resolvewalk caches the array tinfo;
same loud-error rule. Idempotent for the module-level double-call.
- cgenexpr.ww cgdot: the missing wwstage arm for a top-level [N]T
global's .len / .ptr (cstage cgen.c:8011 already had it).
- cgenutil.ww letslotsize: drop the now-redundant [_] slot-size
intercept — a workaround for this very bug; the stamped length flows
through the general slotsize path (rule 7).
Both stages converge byte-identical; new table-driven test 684 covers
[_]int/[_]str/[_]u8 local + module-level, len + element read-back,
dual-stage runtime + asm byte-id, plus three negative no-infer rows.
57 piecewise stderr diagnostics in the checker spelled out
os.write(2, m.ptr, NNu64) with hand-counted byte literals. Replace the
38 hand-counted literal sites and 19 var sites with a tool-local
cerr(m: str) helper that takes .len off the str, eliminating the
off-by-one hazard. All 38 prior hand-counts were already correct, so
stderr is byte-identical. cerr lives in check.ww (not err.ww, which
ports err.c for the dead C-driven path); regen w6c + wwdump
combined.ww.
An empty `[]` carries no element type; ww gets it only from a let
annotation (the #45 retype). Both stages used to silently default the
element to u8, and in value-form positions (return / call-arg) the
lowering miscompiled — malloc(8) ignoring n, a 16B *u8|nomem where a 24B
slice was expected (#5). Now every empty alloc that isn't a
let-annotated binding fails to infer with a loud error, aligning ww DOWN
to harec (ref/harec/src/check.c:1801-1802).
Mechanism: clet / checkletassign flags the single alloc call node that a
`let x: []T =` rescues (save/restore around the init walk); the alloc
branch errors on any empty alloc that isn't that node. The #45 wide-T
retype path is kept. wwstage needs an extra not-yet-stamped guard because
resolvewalk re-types value nodes context-free after checkletassign.
Tests: negative cstage-driver 729 (table-driven: bare-let, return,
call-arg, assignment) + positive @test in attest_pass.ww exercising the
u8 and the wide-i32 (#45) paths at runtime. Both stages reject
symmetrically; byte-id verified on []u8 and []i32.
The wwstage checker rejected a match-bound binder used in a `yield` arm
of a match-AS-EXPRESSION (`let v = match (x) { case let p: *T => yield
*p; ... }`) with asserttyped:un/bin/index; cstage compiled it.
resolvewalk stamps the yield operand's type_ during the in-scope N_MCASE
arm walk. exprtype's N_MATCH arm then derived the match's type by
re-running exprtype on the same operand to recover a type NODE — but the
arm binder's scope is already popped, so the re-derive returned nil and
the N_UN/N_BIN/N_INDEX restamp arms overwrote the good in-scope stamp
with nil. cstage never re-runs: match_yield_type reads the operand's
cached ->type (cmd/wcc/check.c:121).
Root fix (align wwstage UP): matchyieldtype now returns a *tinfo and, at
the post-walk call, READS the operand's cached node.type_ instead of
re-running exprtype — so no operand shape can be clobbered by
construction (deref/bin/index all vanish, no per-arm guards). The
exprtype N_MATCH consumer stamps e.type_ from that tinfo directly (no
tinfofornode round-trip). The pre-walk call (checkletassign L302 /
checkretassign L303 run before the in-scope arm walk, so the operand is
nil there) keeps the nil-safe re-derive — benign and load-bearing: it
types the void-arm literal so let/return-assign has a usable node. The
re-derived node (or btype for the bare-binder idiom) is carried back via
an out-param for the assignability check and for the N_MLET/N_MASSIGN
tuple-destructure consumers (`let (a,b) = match { case let t => yield t
}`, test 945). cstage is single-pass so its else is dead; eliminating
the pre-walk call is #279.
Supersedes the narrow N_UN non-clobber guard (removed — its match
consumer is gone). @test check_match_ptr_deref extended to pin the whole
operand class (deref / bin / slice-index / deref-then-field), dual-stage
(910 + 997) with correct runtime + cs==ww byte-id. The *[N]T ptr-to-
array index variant is blocked separately by #278. Both compiler-
imported combined.ww regenerated. smoke + test-unit (242) + 994 w6c_ww
byte-id (18 corpus incl. selfhost combined.ww) green.
Hare admits an array with a defined length wherever its element slice is
expected (assign / return / call-arg / init) as a borrow; ww rejected it
everywhere (the #108(c) exclusion), so base64 worked around the gap with
explicit a[0:n] slices.
type_assignable / isassignable now admit array->slice on an exact element
match (mirror ref/harec/src/types.c:1080-1097, the SLICE-dst arm). The four
acceptance sites route through one shared helper (desugar_arrayslice /
desugararrayslice) that rewrites the array expr to the explicit full slice
arr[0:len(arr)] — an N_SLICE over the array base. cgen is untouched: the
existing slice lowering (#252/#257/#135 made array bases, incl struct-field
arrays, correct) materialises the borrow header {.ptr=&arr[0], .len=N,
.cap=N}, byte-identically in both stages.
wwstage runs no general call-arg / N_ASSIGN typecheck, so checkassign +
desugarcallargs are added solely to route those two contexts through the
shared desugar (rule-10). desugarcallargs additionally loud-rejects an
element-MISMATCH array into a []T param, scoped to that shape so wwstage's
broader call-arg leniency is untouched.
953_arraytoslice_run covers the four contexts + a borrow-alias proof + the
i32/u8 element axis (dual-stage run + cs==ww byte-id), plus mismatch-reject
rows asserting both stages refuse [4]i32 -> []u8. Regen'd w6c + wwdump
combined.ww (#110).
`let a:[4]u8=[65,66,67,68]`, `def D:[4]u8=['A',..]`, and `enc{m=[65,..]}`
rejected with "init [4]i32 not assignable to declared [4]u8": an array
literal's element type came from the elements via type_default (int-lit
-> i32, rune-lit -> rune) with no declared-element-type propagation. The
scalar path already narrows (`let c:u8='A'`); only array aggregation at
the let/def/struct-field sites #130 (test 920) left unwired did not.
Fix = the int/rune analogue of coerce_floatlit, realised as the EXISTING
#130 accept-if-fits range-check — NOT a node-type restamp. cgen drives
the array element WIDTH from the declared type at every site (cgen.c
local-let lu->sub, emit_array_data d->type), so a restamp would be dead
code (the array literal keeps its [N]i32/[N]rune node type; the cs==ww
byte-id gate confirms the bytes emit u8-wide regardless). Per element:
foldable int/rune literal -> defcastfits range-check vs declared T
(in-range accept, out-of-range REJECT loud, rule-7); non-foldable ->
type_assignable / isassignable.
cstage (check.c): wire arrlit_init_fits into clet (local let),
struct-field-init, and def-init — the three sites the #130 module-let
path already covered.
wwstage (check.ww): factor checkletassign's inline #130 block into
checkarrlitfits and call it from the let path, the def path, and a
TARGETED array-field walk in the N_STRUCTLIT arm. This also closes a
pre-existing rule-7 wwstage over-accept: the def path ran NO init
assignability check and the N_STRUCTLIT head-stamp parks field
assignability (#23), so out-of-range / str array elements silently
over-accepted (a truncating miscompile) at those two sites. The
struct-field walk is the array-field accept-if-fits ONLY — it reuses the
stable N_TSTRUCT field-list walk (astoffset precedent), isolated from
the broader parked #23 field-assignability walk.
Regenerated w6c + wwdump combined.ww (embed check.ww). New test 951
covers let/def/struct-field x int/rune accept (run + cs==ww byte-id) and
out-of-range/str reject (both stages). test-unit 237 + smoke green.
cstage cbinop routes every comparison through unify_arith
(cmd/wcc/check.c:952), which loud-rejects an error-typed operand
paired with a differing type (e.g. strconv.invalid != i32). wwstage
binoptype returned bool for comparisons without any unify step, so it
silently accepted a program cstage rejects -- a rule-10 break (align
the leaner-but-leniner wwstage DOWN to cstage).
Scope the rejection to an error operand (varianterr) mismatched with
the other (typeeqast) so the broad differing-types diagnostic -- whose
typeeqast-vs-cstage-type_eq asymmetry risk could reject valid bootstrap
code -- stays out of wwstage. Covers the whole comparison family
(EQ/NEQ/LT/LE/GT/GE), all of which cstage routes through unify_arith.
Found by impl-strconv3 writing the strconv test. Gate-blind: the
bootstrap never compares an error type to an int, so byte-id stayed
green while the stages disagreed on what's a valid program.
test/wcc/949_errtype_compare.c: both drivers reject invalid !=/==/< i32
(K_BUILDERR); same-error-type and plain-int compares still accept on
both stages + cs==ww byte-id (K_RUN). 12/12.
cgexpr could not produce a tuple VALUE, so a destructure / let bind of an
RVALUE tuple read garbage past the first element (cstage) or left an untyped
binder aborting wwstage's asserttyped gate — a DANGEROUS gate-blind cs!=ww,
and the strconv-int blocker (Hare's stoi64/stou64 require
`let (sign, u) = parseint(s, base)?`). Three feeders, all routed at the same
SysV register-return cursor the cgmlet/cgmassign consumers already read:
- an N_TUPLE literal fell to the `cgexpr_int(0)` / `MOVQ $0, AX` default;
- a tuple-typed IDENT loaded only word0 into AX (`yield t`, `return t`,
`let q = t`), leaving DX/CX stale;
- the `?`/`!` unwrap of a tuple-in-union payload lifted only word0->AX,
stranding word1 in CX (the scalar/str success ABI).
Fix (both stages, byte-identical per rule 10):
- cgexpr packs an N_TUPLE literal into the cursor (cg_tuple_lit_to_cursor /
cgtuplelittocursor — a byte-identical reuse of cgreturn's in-register
N_TUPLE arm) and a tuple IDENT from its slot at the register-ABI stride
(cg_tuple_slot_to_cursor / cgtupleslottocursor);
- the ?/! unwrap shifts a tuple success payload down one integer reg past
the tag (cg_tagged_tuple_payload_shift / cgtaggedtuplepayloadshift),
loud-stopping a float/slice/str payload element (the SysV per-eightbyte
tagged-tuple-payload classification is #243);
- wwstage's checker recovers the popped match-arm binder type for a
`yield <binder>` operand (matchyieldtype's scope-free fallback to the
arm's declared type), so the destructured binders stamp — cstage reads
the operand's already-stamped ->type, wwstage caches only a tinfo.
Over-cap rvalue-tuple materialisation (no slot to sret a bare expression
value into) loud-stops both stages — the #10 follow-up.
NOT closed (distinct root, deferred to #238/task #6): single-var
`let q = (true, 9u64)` then `q.N` — the N_LET tuple-init sz==16||32 gate
drops a narrow-first mixed tuple, and the N_DOT tuple-field PACKED-offset
reader disagrees with tuple_store's 8B stride. Not the rvalue-into-cursor
fix and not a strconv blocker (strconv destructures); documented at the test
header.
Test 945_rvalue_tuple_destructure_run: literal destructure, match-yield
destructure, and the ?-call strconv shape, each run + cs==ww byte-id on both
drivers (9 checks). Embedded w6c/wwdump combined.ww regenerated.
A mixed-scalar tuple WRAPPED IN A TAGGED UNION (the (neg, n) shape Hare's
strconv parseint returns, ((bool,u64)|invalid|overflow)) miscompiled three
ways, all gate-blind (no bootstrap tuple-in-union):
(a) cstage CONSTRUCTION: a tuple variant fell through the N_RETURN scalar
shuffle, which ZEROED tag + payload — the operands were never packed.
Route the tuple variant through the scratch-slot widen path; add a
TY_TUPLE arm to cg_widen_tagged_store that packs each element into the
union payload at the register-ABI 8B stride + sets the variant tag.
(b) wwstage CHECKER: `let (a,b)=t` over a plain tuple ident (the match-
bound union payload) left the un-annotated binders UNTYPED, so the bin
node reading them was untyped -> asserttyped abort. The element-type
distribution only fired for an N_CALL rhs. Consume the rhs tuple type
for ANY rhs (mirror cstage check.c:2017).
(c) BOTH stages DESTRUCTURE: the register-cursor receive assumes the rhs
left every element in AX/DX/CX (a call's tuple-return ABI). For a tuple
IDENT cgexpr loads only word0->AX, so the 2nd binder read a STALE DX.
Copy each element from the ident's slot at the 8B stride.
Construction is correct at ANY variant position (the resolved tag, not a
default 0); wwstage resolves it via the typeeq core (flatvariantidxt), not
taggedvariantindext whose str/slice shape-fallback would mask a mismatch.
Two rule-7 loud-stops cover shapes this slotted packing can't yet handle,
on BOTH stages, so neither silently miscompiles:
- a tuple with a SysV-eightbyte-sharing narrow pair (e.g. (i32,i32,u64)),
caught by the 8+payload > slot-size guard (the eightbyte tuple
classification is #243);
- a tuple built from a BARE LITERAL element (`true`/`false`, suffix-less
`7`). cstage's cg_tag_for_variant can't type the literal (#241), returns
-1, and loud-stops. wwstage types `true` as bool and `7` as untyped_int,
so flatvariantidxt WOULD resolve the variant — a program cstage rejects
but wwstage accepts is the cs!=ww divergence rule 10 forbids. wwstage
mirrors cstage's CONDITION (a bare-literal element), not its -1
mechanism, with an explicit guard that aligns the richer side DOWN. Lift
BOTH guards together when #241 lands cstage literal typing -> symmetric
accept.
Test 940_tuple_in_union: 4 K_RUN rows (variant 0, void arm, tuple at
variant 1 two ways) x cstage-run + wwstage-run + cs==ww byte-id, plus 2
K_BUILDERR rows (eightbyte-share, bare-literal) asserting a loud stop with
the #242 diagnostic on BOTH drivers = 16 ok.
The wwstage checker `fieldslotsize` (check.ww) summed each struct field's
SLOT width to stamp the enclosing struct's tinfo.slotsize, but had no
TY_TUPLE arm — a tuple-typed field fell through to the 8B default. So
`struct { f: ([]u8,[]u8) }` stamped slotsize=8 while size=48 (the natural
element sum, correct). A `let s: S` slot is allocated off ti.slotsize
(cgenutil.ww slotsize), so wwstage reserved an 8-byte frame slot for a
48-byte struct: a SILENT stack-corrupting miscompile.
cstage has no size/slotsize split — it sizes the field at f->type->size=48
throughout — so the stages diverged on the emitted frame ($16 wwstage vs
$64 cstage), invisible to a cstage-only check and caught only by cs==ww
byte-id (rule 10).
Add the TY_TUPLE arm (return the tuple's own slotsize, the per-element slot
sum already stamped at the N_TTUPLE arm with slices at 24 each). This
aligns the checker's field-slotsize with cgenutil.ww fieldsize, which
already returns the tuple's natural size (48). The stale comment claiming
"TY_TUPLE inside a struct currently defaults to 8 in cgenutil" is removed —
fieldsize stopped defaulting to 8 at the 2026-05-23 review.
Test 930 pins cs==ww .s byte-id for a struct with a tuple field (with and
without a leading scalar field, foff 0 and !=0); pure frame-size gate, no
runtime — the divergence is fully visible in the emitted assembly. No
selfhost source has a tuple-typed struct field, so the w6c/wwdump combined
amalgams regen with no asm change (byte-id-neutral bootstrap).
exprtype's N_IDENT branch resolved a bare value-ident through the
flat-scope scopelookup, which bucket-walks and returns whichever
same-leaf symbol heads the bucket (the last-registered one). Under a
foreign curmod that binds a same-named symbol from the wrong module
and drags in its declaration's type: resolving `read` to io.read while
checking os pulled io.read's (size|eof|error) return node, whose bare
`error` then bound strconv.error instead of io.error. The mistyped
union variant made the tagged-tag remap's flatvariantidxt return -1
(correctly: the union held the wrong type), collapsing the tag to 0 —
the #226 fmt cs/ww asm divergence.
Resolve through scopelookupprefer(c.cur, c.curmod, e.str), preferring
the current module, mirroring cstage cmd/wcc/check.c:66
scope_lookup_prefer. Sibling bare-leaf sites already migrated: #56
(N_CALL callee), #53 (bare TNAME).
#226 is thereby an instance of #55, not a nominal-identity gap:
io.error is already a sound sym-cached singleton. The remaining
bare-leaf sites (N_DOT-callee leaf, varianterr, scruttype) and the
cgen-side cgident analogue are tracked separately. fmt's 777/780/781
stay STAGE_CS pending a separate spread-union residual.
test/wcc/794: cross-module bare-leaf value-ident, reject->accept
polarity (w6c_ww must accept the cstage-emitted combined); no byte-id
assertion as the minimal value-ident also trips the open cgen-side
cgident bug.
The wwstage checker walked a match's raw AST variant list and never expanded a ...inner spread variant, so it rejected fmt's match over field = (...formattable | *mods) ('not a variant of scrutinee'). cstage's resolve_type flattens the spread at type-build. Mirror that in the AST exhaustiveness walk (casevariantin + a recursive checkvariantcovered): when a variant resolves to N_TTAGGED via a spread, recurse into its members. Additive + spread-gated -- typeeqast / casevariantpairmatch (#13) / casecovers untouched, so non-spread matches and 990-997 byte-id are unaffected. Also size a spread N_TTAGGED off each flattened member (mirror cstage check.c), dropping the inner union tag word (field 40B to 32B). Closes the #209 CHECKER reject; full fmt-byte-id still awaits cgen cluster #226 (io.read nominal-remap) + #227 (spread-widen ABI), so fmt tests stay cstage-only with retargeted comments. Adds test 792; regenerates w6c/wwdump combined.ww.
wwstage's checker rejected matching an imported union's variants cross-module: casevariantin/casecovers' typeeqast did a raw streq, so a union's bare variant "unsupported" failed to match the dotted case pattern "errors.unsupported" (cstage compares resolved-Type identity, qualifier-agnostic). Add a (module, leaf)-pair fallback after typeeqast: reduce both the case pattern and each variant to (module, leaf) and match on pair equality -- a dotted name keeps its own qualifier, a bare name takes the union's defining module (taggeddefmod, via the aliassym hop chain). This closes BOTH directions: the false-reject of valid cross-module match AND a false-accept of a foreign same-leaf qualifier (case othermod.foo vs errors.error now rejected, matching cstage). Handles the nested errors.error-in-io.error case (the dotted variant keeps mod=errors, not the union's mod=io). typeeqast stays the first check so currently-valid code is byte-id-unchanged; the pair-match fires only on the previously-rejected qualified-vs-bare mix. Wired into casevariantin, casecovers, and the is/as caller. Adds test/wcc/787 (cross-module positive, exhaustiveness, foreign-qualifier reject-guard, dotted-variant body). Unblocks #5's cross-module io.error/errors.error decomposition. rule-10 fix-up; #10-family (wwstage cross-module resolution).
A bare `&fn_name` was not assignable into a `*reader` / `(*reader | void)`
vtable field without an explicit cast: cstage type_eq on TY_NAMED is
pointer-identity, so a structural `*fn(...)` referent never matched the named
`*reader` variant; wwstage accepted it only via an accidental catch-all
leniency. harec accepts bare &fn through hint-directed alias adoption at the
address-of site (check.c:3594-3626) while keeping pointer assignability
strictly nominal (types.c:1039-1066), so a materialized `*fn` value never
launders across alias names.
Mirror that decision without threading a type hint through the bottom-up
cexpr: keep type_assignable / isassignable fully nominal, and add a
caller-site helper (assignable_addrfn) at the assignment boundaries
(let-init, struct-literal field-init, assign, return, call-arg, array
element) that accepts iff the rhs is a DIRECT &-of-fn-ident and the
destination (or exactly one tagged variant) is a pointer-to-fn-alias whose
underlying fn signature structurally matches. A materialized `*fn` value, a
distinct same-signature alias, and an ambiguous multi-variant target all stay
rejected. Both stages share the rule; wwstage's lenient pointer-fn punt
becomes a confident reject. ww has no methods, so a `value.leaf` slot is only
ever a fn-pointer field and this never over-admits.
The tightening surfaced a wwstage typeeqast gap: a TY_FN result that is a
tuple (`*fn(...)(i32,i32)`) compared false where cstage type_eq handled it,
newly rejecting a legitimate structural assign. Add the N_TTUPLE structural
case (rule-10), restoring test 766.
cgen-neutral (the cast was a no-op reinterpret); pre/post bootstrap .s
zero-delta. Test 783 covers the positive paths (incl. a byte-id-clean
three-field-vtable dispatcher) and the negatives. Tagged-slot negatives
(ambiguous / tagged-laundering) are rejected on cstage but wwstage's separate
`(X|void)` void-variant leniency (#214) still admits them; 783 pins them
cstage-only, to graduate when #214 closes (required before wwstage becomes
the authoritative selfhost checker).
Note: `make clean && make test` is RED at HEAD on 4 alloc fixtures
(700/748/758/915) via a pre-existing clean-build defect (#215, malloc vs
rt_malloc); identical with or without this change, so bisect-clean for #206.
wwstage exprtype's N_CALL arm fell into a global-leaf scopelookup for an
N_DOT callee with a value or chained receiver, binding whatever same-named
global headed the scope bucket. Under a late-os combined.ww concat order
this resolved io's `s.read(...)` to os.read (i64) instead of the field's
fn type, so checkretassign confidently rejected a valid tagged return — an
import-order-sensitive false positive. cstage resolves a call result solely
from the callee expr's own type (check.c:1378-1433, mirroring harec
check_autodereference 1566-1581); drop the global-leaf else-arm so value
and chained receivers fall through to the existing fn-VALUE path at
check.ww:2455. SK_USE module-qualified calls are unchanged.
ww has no methods, so `value.leaf()` is only ever a fn-ptr field access; the
global hit was never legitimate. Zero .s delta across all 5 bootstrap tools
(the branch is dead in the bootstrap); test 776 graduates to both stages
(os-late order, byte-identical).
The fix unmasks a pre-existing wwstage cgen bug (#211): cgen also re-derives
a call's return shape by name (fnretlookup), so a value-receiver field call
whose leaf collides with a same-named global of a different register shape
mis-resolves cs!=ww. Documented at the cgen site; pinned cstage-only by
test/wcc/782 (graduates to STAGE_WW on #211 close).
The tagged→tagged subset arm walked src's leaves against dst's flat
variant list, so `let r: (size | eof | wrapper) = e` with e: wrapper
REJECTED at cstage's checker — wrapper's leaves (unsupported, underread,
nomem) aren't direct variants of dst. Wwstage's permissive tail
accepted silently but cgen then miscompiled the tag (#199b layout-
extension family, deferred).
Mirror the concrete→tagged fix from #199 (α) at type.c:316: when src is
a NAMED-tagged wrapper and dst has a direct NAMED-tagged variant equal
to src, accept by nominal identity BEFORE the subset loop. Wwstage's
isassignable mirrors the structural insertion before the existing
`*confident = false; return true;` tail (deferred-tightening per #202).
SSoT with `is`/`as` non-recursive variant lookup (#198 family).
Cgen's tag-remap for the wrapper-as-whole case still maps src variants
to dst tag 0 — the wrapped-slot layout for `dst.tag = variant_idx,
dst.payload = src` is #199b future-work. Probe verifies checker-accept
+ runtime exit-clean only; does NOT inspect the resulting variant tag.
Probe 774_tagged_widen_named_variant.c covers 5 rows: bug-repro,
nested-wrapper, pure-leaf subset (regression), concrete-unrelated
rejection (gate), branched callee. Two sibling cgen/checker bugs
surfaced (wwstage cgwidentaggedstorebp ssz<slot_sz pad gap; wwstage
isassignable !void-alias collapse) and documented inline at the
probe-row comment, kept in #202 family.
checkisas walked the unflattened AST u.list via casevariantin (typeeqast
streq), so any variant introduced via a `...inner` spread was invisible
and rejected as "is/as: not a variant of operand". Repro:
type rsh = (size | io.eof | ...io.error);
let r: rsh = 42: size;
if (r is io.underread) ... -- pre-fix wwstage REJECTS
io.underread is in io.error.params, which tinfofornode splices into the
parent at L1827-1836, but the AST u.list still holds the single
`...io.error` entry that streq("io.underread", "io.error") rejects.
Route through flatvariantidxt — the same Phase-N helper #179 cgmatch
and #66 cgtagvariantidx already key off. Mirrors cstage cmd/wcc/check.c
:1662-1675 u->params + type_eq. Falls back to casevariantin AST walk
when tinfo isn't available (defensive — non-#198 path stays as-is).
project_tinfo_lossy_nominal: name-keying was the pre-Phase-N workaround
for tinfo lossy on nominal identity; typeeq inside flatvariantidxt now
handles NAMED ptr-id (#64), so the checker pair aligns with cgen on the
flattened-variant axis.
Closes the cgen-drain mini-cluster (#201 -> #199 -> #200 -> #198).
773_isas_spread_variant: 5 rows (spread_is_inline_variant,
direct_cross_mod_tagged, cross_mod_named_void, same_module_variant,
spread_as_inline_payload). Rows 2-4 byte-id; rows 1/5 skip byte-id due
to layout-asymmetry on `...wrapper` (cstage flattens at resolve_type,
wwstage computes maxsz off vt.size of the un-spliced alias) — sibling
not blocking the checker correctness fix.
cgen has no wrapped-slot layout — the tagged-union slot is universally
[tag:8B][payload:up_to_24B], single level. The recursive walk admitted
let r: (size|io.eof|io.error) = u for u: io.underread (transitively
in io.error.params); cg_tag_for_variant + taggedvariantindext don't
recurse, returned -1, defaulted to tag=0, and the slot read back as
variant 0 = size at runtime.
Restores SSoT inside the checker pair: is / as / match variant
lookup is already non-recursive (#198 sibling), and the LET-init /
return / assign arms now agree. Aligns DOWN to the leaner side
(rule-10 stage symmetry). ww-stricter than Hare; harec keeps the
drill at ref/harec/src/types.c:702-739 (#199b is the deferred
wrapped-slot layout port).
Pre-flight audit (drew mandate): zero transitive-widen sites in
lib/ + selfhost/ + cmd/ + examples/. No wrapper-tagged variant
(io.error, strconv.error, fmt.field) is used as a variant of a
wider union anywhere in bootstrap. Mechanical fix.
Escape hatch for callers: spread (...wrapper) inlines the wrapper's
flat variants into the parent set at parse time. Wwstage's gate
additionally preserves the recursive drill on op == TK_ELLIPSIS
because wwstage stays AST-keyed (cstage flattens at resolve_type).
771_widen_transitive: 5 rows (reject_transitive_widen,
spread_alt_widen, direct_flat_variant, branched_callee_widen,
wrapper_typed_widen). Row 2 is CS-only — wwstage's is / match on
spread-expanded variants is open-bug #190/#198.
Pre-fix the wwstage checker bailed asserttyped on the N_CALL whose
callee was N_UN TK_STAR over a *fn — selfhost/cmd/wcc/check.ww
exprtype's N_CALL arm only resolved IDENT/DOT-named callees and
early-returned nil for any other shape, leaving e.type_ unstamped
so the post-checker invariant fired. cstage worked because cexpr
recurses on the callee — TK_STAR's unop arm returns t->sub which
IS the TY_FN, no name path needed.
Fix: replace the `if (nm.len == 0) return nil` early-bail with
`if (nm.len > 0) { name-lookup }`, so non-named callees fall
through to the existing fn-VALUE fallback below (peel TPTR /
dealias to TFN / stamp the result type). Mirrors harec
check_autodereference at ref/harec/src/check.c:1566. cgen post
-#180+#185 already lowers the deref-call correctly, so lifting
the asserttyped bail is silent-SIGSEGV-safe per drew + ken.
Combined.ww regenerated for selfhost/cmd/{w6c,wwdump}/main
.combined.ww per #110 freshness gate.
Probe: test/wcc/766_star_fn_deref_call.c, 5 rows table-driven —
minimal / branched-callee / alias-chain / fn-with-args / fn
-tuple-return. Gate flip from 765: every row now gates BOTH
stages — cstage runtime, wwstage runtime, AND cs.s == ww.s byte
-id. This is the runtime coverage 765 deferred plus the symmetry
gate that proves both stages emit identical asm for the deref
-call shape. Closes the full c-cluster (#180 + #185 + #181 all 3
commits working together end-to-end).
Pre-fix master left N_TFN under typeeqast's conservative
"anything else fails" tail (selfhost/cmd/wcc/check.ww:748-751).
case-patterns spelled with a raw `*fn(...)` head — the io vtable
use case — tripped casevariantin / casecovers on every variant
compare, so a well-typed `match (v: tagged-of-fn-ptr) { case
*fn(...) => ... }` would not compile under wwstage.
Adds a TY_FN arm that mirrors harec STORAGE_FUNCTION
(ref/harec/src/types.c:589-615): recurse on the result type
(.lhs), iterate the param chain (.list of N_PARAM, descend each
.lhs), require the variadic flag (.op == TK_ELLIPSIS) to match
position-by-position, and require both chains to terminate
together. Param NAMES do not participate (harec analog), and the
C-variadic terminal sentinel (N_PARAM with .str == "...") is
handled defensively even though wwstage's parseparams doesn't
currently produce it. Attributes + default-param values are NOT
checked (drew-pre-approved, harec doesn't either).
cstage type.c:239's type_eq walks the same shape on the resolved
Type. typeeqast lives one layer below — a documented divergence
filed as project #178 for the harmonization fold; the in-source
comment cites #178.
Probe 763_typeeq_fn_ast.c locks 7 rows covering identical /
diff-return / diff-arity / diff-param-type / variadic / param-
name-only / io-vtable shapes across cstage + wwstage (14
fixtures). Pre-fix wwstage red-errors every row at the checker
("case: not a variant of scrutinee" + "match: variant not
handled"); post-fix all 14 compile and the tag-0 arm fires
(exit 7). Per-row .s byte-id is intentionally NOT gated — see
the probe header for the cgmatch N_TPTR-not-routed-to-
flatvariantidx sibling bug that drives the divergence on rows
b/c/d/e/g; orthogonal to this AST-layer typeeqast fold and not
swept per the brief's "do not sweep" instruction.
The wwstage asserttyped pass only WARNED on a checked value-node with no
result type_, a check-bail-discipline regression that let gate-blind nil-stamp
miscompiles ship green (the whole #6 arc: tuple/struct/fn-ptr/enum/binding
nil-stamps were all invisible to the byte-id gates). With every nil-gap class
now stamped (module-qual calls, fn-ptr-field calls, computed enum value-exprs,
for-range/massign binds) the bail can finally arm: warn -> os.exit(1).
Exempt exactly the two legitimately-no-type value classes, each a positive
cited assertion (never a residual warn): the EXPR_ASSERT family (abort/assert,
guarded against a user shadow; harec check.c:877,893) and seeded pseudo-builtin
callees (len/append/free/alloc/size — a structural nil-decl-SK_FN predicate,
not a name-list). The pre-existing module-ref and dot-lhs filters stay: they
identify access-path components that aren't value exprs (harec EXPR_ACCESS),
not exemptions.
Verified clean over the broadest net — the armed checker over all five
self-build combined units (the full selfhost source) plus the 901 gap corpus —
zero out-of-class bail; fails-loud confirmed (undeclared call, abort's args, a
nil dot-base all bail). Checker-only: 990-997 byte-id hold.
For-range tuple-destructure binders (for (let (k,v) .. s)) and the tuple
massign discard _ were left nil-typed: the for-range binders are N_IDENT
use-sites and the _ slot, though unbound, has a real element type. Add a
shared stamptuplebinds helper — one lockstep walk distributing an N_TTUPLE's
per-element types onto a binder chain — refactoring the existing N_MLET
destructure loop into it (behavior identical) and adding N_FORRANGE and
N_MASSIGN call-sites. _ is STAMPED with its slot's element type (unbound is
not untyped), not exempted. Mirrors harec create_unpack_bindings
(ref/harec/src/check.c:1354-1419), the routine harec shares between let-unpack
and the for-each header (:2308-2317).
A prerequisite for arming the wwstage asserttyped bail. byte-id holds (cgen
derives binder/elem widths structurally, never off type_; 990-997 green).
Extends the 901 gap-corpus with 901_forrange_tuple.ww + 901_massign_blank.ww.
A computed enum member — B = A + 4, RW = R | W, sibling/chained backref —
left its value-expr node nil-typed: enumvalfold folds the constant but never
stamps the expr, and since enum members are not installed as scope idents the
sibling backref resolves to nothing, so BOTH the N_BIN/N_UN wrapper and the
backref N_IDENT go nil (literal members are fine). Stamp the value-expr subtree
(only-nil) to the enum's underlying storage type via a new
stampenumvals/stampnilexpr pass on the N_TENUM branch. Mirrors harec checking
each member value-expr at the underlying type (ref/harec/src/check.c:4419).
A prerequisite for arming the wwstage asserttyped bail. Checker-only — the
value folds to a constant at every use site and in cgen, so the node's type_
is never read by codegen; 990-997 byte-id hold. Extends the 901 gap-corpus
with 901_enum_corpus.ww.
A call whose callee is a fn-VALUE (a fn-pointer struct field like w.emit(...),
or a local/param) had no free SK_FN entry, so exprtype's name lookup missed and
the N_CALL went nil-stamped (the fn-ptr-field class of the asserttyped gap
audit — 3 warns at smoke). When the name lookup misses, fall back to harec's
check_expr_call shape: read the result off the checked callee node's own type —
autodereference + dealias to the TY_FN, take its result (ref/harec/src/check.c
:1566-1581). Name lookup stays primary: a fn-NAME callee node carries its
return type, not its fn-type, so an N_TFN check first would mis-yield void for
a fn-returning-fn; only genuine fn-value callees reach the fallback.
Drives the 901 gap-corpus B count to 0 — with A/D already closed, only the
legitimate abort exemption (C) remains before the bail can arm. Byte-id holds
(cgen's fn-ptr detection is structural, independent of the stamp; the lib/io
return-forwarding site is cs==ww on both bootstrap combined.ww).
The wwstage checker resolved a module-qualified call/access mod.x by the
same-module preference in scopelookupprefer, so when the importing package's
name collides with a type/fn of the same leaf (package fnmatch with fn fnmatch;
package random with type random), the dot-lhs mod resolved to the same-leaf
SK_TYPE/SK_FN instead of the coexisting SK_USE import — the N_DOT module-qual
arm never fired and the call went nil-stamped (the D class of the asserttyped
gap audit: fnmatch 2, random 16). cstage resolves this via Sym.use_alias; this
ports the equivalent to wwstage.
Add scopelookupuselocal (a single-scope SK_USE lookup, twin of scopelookuptype)
and prefer SK_USE for a dot-lhs in exprtype's N_CALL and N_DOT arms, keyed on
the scope where scopelookupprefer landed so a local binding sharing a module's
leaf keeps value semantics. Scope-layer only — no type-identity touch (cstage
use_alias never reaches type_eq).
Drives the 901 gap-corpus D count to 0 (random_test now byte-id cs==ww).
Compiler binary unchanged (no such collision in its own source); 990-997 hold.
The separate fnmatch bare-enum-member cgen cs!=ww is unrelated (filed).
Re-arming the wwstage asserttyped bail surfaced 94 nil-stamp warns in the
checked corpus: let (a,b) = mod.fn() left its destructure bindings (and every
use) unstamped because exprtype's N_CALL arm resolved an N_DOT callee by bare
leaf — the gap its own comment flagged (#16/#17). Fix at the root: when an
N_DOT callee's lhs resolves to SK_USE, resolve the result via
scopelookupinmodule (mirror cstage cexpr check.c:1035 + cgen fnretlookupmod
cgen.ww:2263). The N_MLET backfill then just consumes the resolved tuple,
matching harec create_unpack_bindings (check.c:1354-1419), which does no callee
resolution — single path, no third copy.
The SK_USE gate leaves the module-leaf==type/fn-name collision cases
(random/fnmatch) on bare lookup — that nominal-resolution gap is a separate
fold. Beyond destructure, the root fix also closes a latent cs!=ww divergence
on non-destructure cross-module same-leaf calls (a head-ordered shadow was
mis-sizing the receive slot).
asserttyped is ww-stage only, so the live ww-driver suite can't see this — the
net is the warn count (checked 94->0, collision cases unchanged) + cs==ww .s
(probe 956). Compiler binary unchanged; 990-997 byte-id hold.
resolvewalk N_MLET arm distributes the N_IDENT-callee rhs return-tuple
element types onto unannotated bindings (the A-narrow slice). Byte-id-
neutral — cgen still classifies structurally, stamps inert until the
exprfloatkind collapse. N_DOT-callee destructure deferred to #16/#17.
Prereq for the #121 collapse (commits 2/3).
fold-1 narrows a float literal at materialisation only when its node
already carries an f32 type — the `f32` suffix. The common un-suffixed
case `let x: f32 = 1.0` stays ty_untyped_float through the checker, so
the node is never f32-typed: the literal materialises as a 64-bit double
and the f32 consumer reads the low 4 bytes (0.0f for clean values).
Stamp such a literal f32 when an f32 target type is in context, the way
harec's lower_implicit_cast does (ref/harec/src/check.c:148): a float
literal's bit pattern is target-dependent, unlike a width-agnostic int
immediate, so the value-producing node must carry the type. Scoped to
untyped_float -> f32 only (f64 already works via cgen's double default).
coerce_floatlit (cstage clet + cstmt N_RETURN) / coercefloatlit (wwstage
resolvewalk's post-order N_LET / N_RETURN handler) are logically
identical. The wwstage stamp is placed AFTER the child re-walk: the
post-order exprtype dispatch re-stamps a bare N_FLOATLIT back to
untyped_float, so coercing earlier (checkletassign) would be undone.
Scope is let-init and return ONLY, aligned down to the leaner wwstage
(rule 10). The wwstage cgen's exprfloatkind hardcodes a float literal to
f64 and cgbin / the unary negate pick f32 off the operands, not the node
stamp — so a stamped literal in an arith-binop / behind a unary minus
narrows in cstage (ADDSS) but not wwstage (ADDSD), a byte-id break. The
wwstage checker also has no assign / param-typed call-arg / per-field
struct-lit site. binop, unary-minus, assign, call-arg, struct-field wait
on #120 (wwstage cgen + checker build-out).
965_f32stamp_run: cstage run + cs==ww byte-id over un-suffixed let-init
and return literals, the hole 964 left open. Regen w6c/wwdump
combined.ww embeds.
#108 sub-fold (b): close the footgun #108(a) opened. opaque is abstract
and UNSIZED (size = align = SIZE_UNDEFINED = (u64)-1), legal only behind
indirection. Without guards a bare use would fabricate a (u64)-1-byte
slot — a silent miscompile (rule 7). opaque is illegal by-value in FOUR
aggregate positions (array element, struct field, tuple member, tagged-
union variant) + as a bare value, under size/align, and as a []opaque
element-index. LOUD guards, mirroring harec's scattered `size ==
SIZE_UNDEFINED` checks:
1. bare value/local/param/return-by-value (check.c clet, build_fn_type,
top-level let; harec check.c:1524, :3931)
2. opaque struct field (resolve_type N_TSTRUCT)
3. [N]opaque array element (resolve_type N_TARRAY)
3t. opaque tuple member (resolve_type N_TTUPLE;
harec type_store.c:1147)
3u. opaque tagged-union variant (resolve_type N_TTAGGED;
harec type_store.c:449)
4. size(opaque) / align(opaque) (size/align fold;
harec check.c:2720)
5. indexing []opaque (N_INDEX; harec check.c:384)
Detection is via the SIZE_UNDEFINED sentinel the guard consults, so the
sized forms `*opaque` (8B) and `[]opaque` (24B header) pass untouched.
Rule-10 per-guard stage placement:
- Guards 1/2/3/3t/3u/5 are CSTAGE-ONLY. The wwstage check.ww is an
AST-level approximation with no binding-size computation (g1) and no
type-decl field/element/member validation walk (g2/g3/3t/3u); its
N_INDEX indexresult returns the element type without consulting its
size and defers invalid-index rejection to the cstage (g5). Same
cstage-only neg-case precedent as 712_redecl / 708_param_shadow_mod.
- Guard 4 is BOTH-STAGES. The wwstage HAS the size()/align() fold
(astsize/astalign would otherwise fold opaque to a bogus 0 — a silent
miscompile); twinned via astunsized + deffolderr. Because the wwstage
has NO per-construction guards, its fold alone must catch every
opaque-containing type: astunsized is RECURSIVE — a type is unsized
iff it is opaque OR an aggregate (array/struct/tuple/tagged) with a
recursively-unsized member. This both reaches the tuple/tagged folds
AND closes the leaf-only size([4]opaque)/size(struct{x:opaque})→0
leak. The cstage size/align guard stays leaf — the cstage rejects
unsized aggregates at construction, so its fold only ever sees a leaf.
opaque is unused by the bootstrap, so every guard is inert on the
selfhost corpus — 990-997 stay byte-identical. Regenerates the w6c/wwdump
combined.ww (check.ww embed). New compile-fail probe 961_opaque_guards
(14 build-fails rows incl tuple/tagged/nested + 2 *opaque/[]opaque
positive controls); 960 positive probe unchanged.
#108 sub-fold (a): TY_OPAQUE exists, is name-bindable, and carries an
UNDEFINED size sentinel. Mirrors the #85 `size` fold pattern at every
site, both stages (rule-10).
opaque is abstract + UNSIZED: prim()'d with size=align=SIZE_UNDEFINED
(NOT 0 — a 0 would let a bare `let x: opaque` fabricate a 0-byte local),
mirroring harec builtin_type_opaque (ref/harec/src/types.c:1446). ww had
no incomplete-size sentinel, so this fold ADDS one: cstage
`#define SIZE_UNDEFINED ((u64)-1)` (== harec types.h:58 (size_t)-1) and
wwstage `def SIZE_UNDEFINED: u64 = 18446744073709551615`.
Legal only behind indirection: `*opaque` (8B ptr) and `[]opaque` (24B
slice header) construct correctly because type_ptr/type_slice (and the
wwstage typeptr/typeslice) size themselves independent of the element.
opaque is deliberately absent from is-int/unsigned/num/float and from
the size-classification switches (let_emit_size / tupleelemslot /
fieldslotsize) on both stages — it only reaches those as TY_PTR/TY_SLICE.
The use-restriction GUARDS (reject bare opaque / size(opaque) / opaque
field / [N]opaque / []opaque-indexing), assignability, and cgen-verify
are the separate sub-folds (b)/(c)/(d) — NOT here.
opaque is unused by the bootstrap, so 990-997 stay byte-identical
(inert, like #85). Regenerates the w6c/wwdump combined.ww (typ.ww +
check.ww embedded). New probe 960_opaque_decl_run exercises `*opaque`
and `[]opaque` (.len/.ptr) behind indirection.
Resolve `size` -> TY_SIZE at the type-name resolver (C lookup_builtin /
ww tinfofornode's N_TNAME chain), mirroring uintptr, both stages. This
makes `size` writable as a type (`let x: size`, struct field, etc.),
the prerequisite for lib/types SIZE_MAX.
Twins every NAME-keyed uintptr arm in the wwstage so it behaves like
the cstage's kind-keyed Type switches (already TY_SIZE-aware from
fold-1): primtypesize + astalign (8B/8-align), primsize + letscalarprim
(8B scalar slot), isinttypeast + isnumerictname (int/numeric). rule-10
symmetric; dead on the size-free selfhost corpus so 990-997 stay byte-id.
Coexists with the size(T) size-of operator (separate c.top SK_FN seed +
N_CALL fold, NOT a type path) and `.size` field access (N_DOT); neither
touched. No c.top SK_TYPE "size" seed (would collide with the operator
seed at check.ww:96). Regenerates w6c/wwdump combined.ww (checker
embedded). New probe 957_size_type_run exercises type-position `size`
and the operator in one scope.
