Mirrors the existing abort/assert gates in cstage check.c (strict
same-module lookup rather than scope_lookup_prefer, since lib/os.alloc
under a `use os;` import must not suppress the bare-alloc builtin in
client code). cgen.c shadows the resolution: only fire the rt_alloc
path when the typer left N_CALL.lhs->type == ty_err. wwstage gets a
new samemodfn helper for the matching gate.
Test fixtures: package-main repair for the 3 alloc rows in 700_e2e.c
that the parser was inheriting curmod="os" from the concat'd os.ww;
new shadow-test row asserts a same-module `fn alloc(n: i64) i64`
beats the builtin in cgen.
Per CLAUDE.md rule 10, align cstage down to wwstage — when every
variant in a `?` propagation maps to itself, the remap loop emits
zero JMPs and the propret label is dead. Lazy-allocate it so the
label-counter ID is only consumed when at least one JMP fires.
Smoke test selfhost/test/trypromote.ww exercises same-shape
(i64|nomem)→(i64|nomem) propagation; cstage and wwstage now emit
byte-identical asm for the TRYPROP region.
Single-peel TY_NAMED.under bottoms out at the inner alias when
chain length is 2+, surfaces in two stages with different
mechanisms: cstage's gates inline `if (t->kind == TY_NAMED)
t = t->under` at every callsite (cgreturn, cglet sizing, cgexpr
N_DOT, cgassign N_DOT, cg_sret_retsize) — graduated to a
while-loop via new type_chase_named helper across 11 sites.
wwstage routes all field-walks through structlookup, which
registers only direct struct definitions (not aliases) — missing
the alias-recurse fallback. New structlookupchain helper mirrors
slotsize's N_TARRAY arm precedent; sretretsize + 4 cgenexpr.ww
sites route through it. Splitting would either land cstage
without unblocking wwstage's strings.tokenize wrapper shape
(rule 10 byte-id regression) or land wwstage without cstage
gate parity (breaking 995 self-rebuild). 756 sentinel exercises
4 rows × cstage RC + wwstage RC + byte-id = 12 fixtures; pre-fix
rows 2 + 4 (slice-fields single alias, i32 double alias) fail
on both RC and byte-id. The ~67 cstage / ~26 wwstage candidate
sibling sites are #17-style structural-close follow-up; this
commit fixes the immediate strings.tokenize-wrapper blockers.
Latent #21 has two surface shapes — register polarity in cgun
TK_AMP N_INDEX's complex-base arm, and indexbaseesz's
over-broad .ptr pseudo-field gate — that share a single semantic
path: &N_DOT[N_INDEX] where the inner N_DOT cannot be peeled
into a plain ident base. Polarity-A (cgenexpr.ww) lifted to
cstage's three-line shape; stride-B (cgenutil.ww) narrowed so
the .ptr arm only fires on actual str/slice inners and falls
through to the generic struct-field arm for struct N_TNAME
bases. The fixes compose at the same call site (esz from
indexbaseesz, then the IMULQ-or-elide gate, then complex-base
emit), so splitting them into two commits would leave a
half-fixed intermediate — neither half stands alone as a
bisect-clean closure. Sentinel 755_amp_dot_idx exercises both
shapes across 4 stride classes (slice-elem 24, struct-elem 16,
u8 stride-1 elide, i64 stride-8); pre-fix 5/12 fail, post-fix
12/12 ok. Latent silent miscompile in lib/memio + lib/bufio's
.ptr[i] shape also unmasked.
Cstage and wwstage share the latent: check.c's N_INDEX bespoke
TY_PTR-over-TY_SLICE clause peeled the slice in `*[]T[i]` and
returned the element of the element, while wwstage's elemsizeof
had no N_TSLICE arm for the post-N_TPTR-peel elem and fell to
the 8B catch-all. Splitting leaves one stage broken on the
exact `*[]T[i]` shape the new 754 sentinel asserts byte-identical
between stages (rule 11). The companion 24B per-element copy
emit is a separate codegen wedge already pinned inline at
cmd/w6c/cgen.c:6518; out-of-scope here and noted in the fixture
header.
Structural close of the #4-trio convenience-wrapper audit. Session-6's
#4-trio + #11/#16 graduated individual lookup helpers (fnret/fnparams/
enum/struct/def) to same-module-first via *mod variants. The close
didn't enumerate every cgcall-context callsite — convenience wrappers
that take a *node callee and probe its return shape via bare-leaf
fnretlookup stripped the N_DOT module hint, same wedge shape as #16
(callee_variadic_param, d9b0c90) through a different family of
consumers.
Eight LATENT sites in selfhost/cmd/wcc fixed (each mirrors #34's
nodeisslice two-arm route — N_IDENT uses cmod=c.curmod, N_DOT uses
cmod=callee.lhs.str, terminal call routes through fnretlookupmod):
- cgenstmt.ww cgreturn forwardtagged probe
- cgenstmt.ww cgmlet tuple-return shape probe
- cgenexpr.ww cgdot fn-rvalue probe (mod.fn LEAQ)
- cgenexpr.ww cgtryprop succisstr probe
- cgenexpr.ww cgtryunw succisstr probe
- cgenutil.ww callsretsize (sret arg-prep)
- cgenutil.ww inferletcalltype (let x = f()? tnode)
- cgenutil.ww rhstaggedabicall N_CALL branch
cstage carries no sister bug: cmd/w6c/cgen.c reads every callee
return shape from the typed n->lhs->type per TY_FN sig. Mirror of
#4d/#28/#31/#34/#16 cstage no-sister notes.
753_convwrap_audit: table-driven sentinel exercising cgmlet's tuple-
shape probe. alpha exports foo() (i64, str); beta exports foo()
(i64, i64); main calls beta.foo() — source order puts alpha LAST so
alpha.foo prepends to head of c.fnrets, pre-fix bare walk picks
alpha's str-branch dispatch for beta's call. Post-fix routes to
beta.foo via fnretlookupmod. Asserts MOVQ\\tCX, absent in main.run
TEXT (no str.len store; would fire pre-fix). Remaining 7 sites
covered structurally by shape-mirror — single wedge shape, single
exercise.
make test 127/127; ww2==ww3==ww4 byte-id holds via 995_self_rebuild.
contains(s, needle: (u8|[]u8)) -> contains(s: []u8, needles:
(u8|[]u8)...) bool per ref/hare/bytes/contains.ha:6.
Body: for-loop over needles.len; inner match (needles[i]) with u8/
[]u8 arms each forwarding to index(s, ...) with early return true
on the i32-match arm. 0-arg returns false per Hare spec. Mirrors
sister #9 strings.contains body shape modulo element type.
Sister of #9 (7c5463c). Element shape (u8|[]u8) — slice payload +
scalar u8 — structurally distinct from (str|rune). Was flagged as
potential new-latent surface; verified clean by 967_bytes_run +
cross-module 750_mklabel_modscoped[bytes_strings_contains] +
995_self_rebuild byte-id. No cgen wedge fired — #15 frame growth +
#12 sum-tag forward + #16 fnparamslookupmod close it on the slice-
payload variant too.
contains_cases adds 5 variadic rows (signalled 1700+i): 0-arg false,
1-arg slice hit, 1-arg u8 hit, 3-arg mixed middle-hit, 3-arg all-miss.
Module-header non-variadic divergence note removed.
make test 126/126; ww2==ww3==ww4 byte-id holds via 995_self_rebuild.
Latent silent miscompile surfaced by worker-strcontains3 attempting
strings.contains tagged-variadic graduation: wwstage cgcall's
callee_variadic_param helper (cgenutil.ww:60-70) consumed the N_DOT
callee's leaf via callee.str but routed bare fnparamslookup — bypassed
the module hint at callee.lhs.str. When two modules export same-leaf
fns with differing variadic shapes (e.g. strings.contains(str|rune)...
+ bytes.contains scalar (u8|[]u8)), the bare walk returned the wrong
fn's params for arg-prep while the CALL targeted the correct
module-qualified symbol — ABI mismatch.
Direct sister of #34 (049ebc1) which graduated fnret's N_DOT arm
through fnretlookupmod. #4d's commit body (862715d) explicitly
deferred callee_variadic_param's *mod re-routing pending "future
stdlib port introducing a tagged-vs-scalar or variadic-vs-non-variadic
same-leaf N_DOT collision shape." This is that surfacing.
cgenutil.ww: split callee_variadic_param on callee.kind. N_IDENT stays
on bare fnparamslookup (same-module-first post-#4d). N_DOT routes
through fnparamslookupmod(c, callee.str, callee.lhs.str), pattern-
identical to cgcall's N_DOT branch at cgenexpr.ww:2922-2935.
Cstage cmd/w6c/cgen.c:4279-4302 reads callee params via typed AST
(n->lhs->type + cu->params) — module-aware natively, no sister
change needed (mirrors #4d/#28/#31/#34 cstage no-sister notes).
752_modparam_callee: table-driven 3 rows x 2 stages = 6 fixtures.
cross_module_same_leaf_variadic_vs_scalar (the wedge),
same_module_same_leaf (no-regress), bare_leaf_no_collision (control).
#17 filed for the wider convenience-wrapper audit (enumerate all
wwstage cgen* helpers that take *node and do bare-leaf lookups; sweep
for N_DOT-arm omissions). This commit is narrow to callee_variadic_param.
make test 126/126; ww2==ww3==ww4 byte-id holds via 995_self_rebuild.
index(haystack: str, needle: (str|rune)) (i32|void) per
ref/hare/strings/index.ha:10. rindex symmetric per :22.
Returns RUNE-index (not byte-index) per Hare contract. str-arm reuses
byteindex/rbyteindex for the anchor byte offset, then walks iter
forward counting runes until position(&it) >= bo. rune-arm forward-
iterates with next(), counts rune positions.
rindex_rune divergence from ref/hare/strings/index.ha:45: Hare's
rindex_rune walks i = len(s) - 1 by 1 per step (byte-len-1 minus
decrement count) — neither pure-byte nor pure-rune for multibyte
input, contradicts its own docstring's rune-wise claim. ww honors
the docstring contract: forward iter + last-match-index. Cited
inline at strings.ww.
Unblocked by #13 (d2c64bc) — pre-#13 the test rows
"strings.index" + "bytes.index" would collide on
*.index_match_next_1 labels in combined.s.
index_cases + rindex_cases per-row inline-match (sister convention of
byteindex_str/rune_cases at stringstest.ww:147-231; sum-type-needle
single-struct table awkward). Bisect via signalled = 1400+i / 1500+i.
Rune-vs-byte pin rows: "こんにちは"+"ちは" → 3 (byte 9),
"またあったね"+"た" rindex → 4 (byte 12). Void miss + 4-byte rune
multibyte coverage.
make test 125/125; ww2==ww3==ww4 byte-id holds via 995_self_rebuild.
Latent surface from #15: cgcall variadic-gather block read seq from
n.uval, which post-#15 is always 0 because scanlocals (which used to
stamp it during pre-pass) was deleted. Every variadic callsite in a
fn aliased to @vararg_d_0 / @vararg_sl_0. When two callsites in one
fn had differing arities, the second hit #15's first-use+fail-loud
guard ("localadd: @-prefix slot grew within fn") — correctly, since
the slot was being asked to grow mid-fn.
Fix: read seq from c.varargseq + bump in cgcall's gather branch.
Mirrors cstage's mklabel("vararg_d/sl") natural seq bump.
cgeninit zeroes c.varargseq per-fn (existing), so the counter is
correctly per-fn scoped.
cgen.ww varargseq comment refreshed — replaces stale "bumped only at
emit time" misclaim with the post-#15 per-call shape + the #15
grow-on-pin discipline that surfaced the wedge.
751_vararg_seq_percall: table-driven 3 rows x 2 stages = 6 fixtures.
mixed_arity_two_calls (the wedge), same_arity_two_calls (no-regress),
three_arity_drift (1/2/3 mints @vararg_d_0/1/2).
make test 125/125; ww2==ww3==ww4 byte-id holds via 995_self_rebuild.
Surfaced by worker-strcontains2 attempting strings.contains tagged-
variadic graduation — mixed-arity spec test rows triggered the wedge.
Unblocks #9 + #10 (strings/bytes.contains).
Latent silent miscompile: cstage + wwstage mklabel emitted
<fn>_<prefix>_<seq> with no module qualification, so two top-level
fns sharing a leaf across modules (e.g. bytes.index + strings.index)
emitted colliding labels into the same combined .s. Last assembler
symbol-definition won; JNE/JMP rel32 resolved to the wrong fn's body.
Repro (HEAD pre-fix): two_modules_same_leaf row in 750 — mod1.locate
+ mod2.locate sharing match-over-(u8|[]u8)+for shape. mod1.locate's
JMP misresolved into mod2's body, exit 10. Post-fix: exit 0.
Latent already at HEAD: bytes.contains_match_next_1 +
strings.contains_match_next_1 collide today but the corpus had no
forwarding path that surfaced it.
cmd/w6c/cgen.c + selfhost/cmd/wcc/cgen.ww mklabel: prepend
<module>. when c->cur_mod / c.curmod non-NULL/non-empty. Plan-9
convention extension: TEXT directive already uses <module>.<fnname>
(lex.c:18 a_isidcont accepts '.'); mklabel now mirrors that for
local labels. Both stages symmetric per rule 10. Fragment input
(no `package`) collapses to pre-fix shape — no cross-unit risk.
750_mklabel_modscoped: table-driven 3 rows x 2 stages = 6 sub-cases
(two_modules_same_leaf, bytes_strings_contains, same_module_same_leaf
non-regression). All required substrings asserted via grep + runtime
rc check.
make test 124/124; ww2==ww3==ww4 byte-id holds via 995_self_rebuild.
@-prefix slot keys (cg_tagbase, cg_tagscr, @retscr) are orthogonal
(local_alloc keys, not mklabel emissions).
pushargsrev's widening detection was N_IDENT-only — N_INDEX of a
sum-typed slice element fell through to the scalar widening branch,
which hardcoded the param's first-variant tag (MOVQ $1, AX) and
pushed AX as a single scalar word. Callees that match-dispatched
on the runtime tag always ran the static-guess arm on garbage.
cstage knew the arg's type via check.c so its widen[] flag stayed
off and the natural-push tagged-arg arm pushed CX/DX/AX (high → low)
high → low. wwstage now mirrors via two narrow arms in pushargsrev:
the aistagged guard treats N_INDEX-of-sum-typed-element matching
the param slot as already-tagged, and the natural-push fallthrough
emits PUSHQ CX / DX / AX for the same shape. Both arms gate on
istaggedtype(indexvaluetnode(arg)) so literal- and ident-source
sum args stay on their existing paths.
Sentinel 749_sumtype_forward table-drives the three forward shapes
(N_INDEX, N_IDENT, literal) and asserts per-stage runtime plus a
byte-id window over the callsite asm.
Combined.ww regen for wwdump_ww and w6c_ww follows the cgen source
change; smoke.combined.ww unaffected.
Tests: 123/123 pass; bootstrap fixed point holds (ww2==ww3==ww4).
Subsumes #36. Drop wwstage scanlocals pre-pass; both stages converge on
first-use+fail-loud frame growth, rule-10 polarity DOWN to leaner side.
#36's surfaces (frame-total divergence on match-arm case-let; sibling
offset divergence in variadic+iter+match-prev compositions) close
naturally — running-max c.frame includes every first-use binding.
selfhost/cmd/wcc: add atlocals persistent @-prefix registry surviving
cgblock save/restore; add cgoutbuf/cgoutmode/cgout_enable/disable/flush
for deferred prologue (emit body to buffer, finalise c.frame, then
TEXT/SUBQ + flush); localadd @-prefix dedups against atlocals +
fail-louds on size-grow (rule 7 — no silent truncate); cgreturn-tagged
routes through @retscr (was colliding with @tagscr on arg-widen sizes);
variadic gather esz uses raw primsize (rune->4) not slotsize (rune->8)
— matches cstage and fixes the #36 sibling runtime miscompile in
non-leaf variadic+iter+match-prev callees.
cmd/w6c/cgen.c: drop the over-allocation hack ("for byte-id with
wwstage scanlocals reservation") since wwstage no longer over-reserves;
add fail-loud on @sretscr size-grow; @tagscr sites pass actual slot_sz
instead of stale c.tagscrsz.
748_size_strategy_convergence: table-driven 4 rows x 2 stages
(tag_variadic_runearm, trim_iter_match_prev, variadic_gather_rune_stride,
leaf_baseline). Each exercises a #36 surface shape; 8/8 ok.
Net -1565 lines. Sister latents filed as cosmetic (cs/ws frame size
drift on multiple-variadic-call fns): labelseq drift + varargseq
stuck at 0 — both bootstrap-byte-id safe (ww2==ww3==ww4 holds since
both ww2 and ww3 are wwstage outputs).
make test 122/122; ww2==ww3==ww4 byte-id holds via 995_self_rebuild.
cstage Sdef walk #2 N_DOT branch used c->cur_mod where n->lhs->str is
the correct module hint. Sister of #4c wwstage graduation; same shape
as the TY_FN branch which already uses mafn(c, n->str, n->lhs->str).
cmd/w6c/cgen.c: add sdef_mod_match_hint(s, hint); walk #2 routes hint
first then head-pick fallback, matching #4a/#28/#31/#34 *mod variant
pattern. selfhost: add deflookuprhsmod(c, name, mod); cgdot N_DOT
mod-qualified str-def value-load routes through it. Rule-10 symmetric
stages: both stages now share the lhs.str polarity (was: both used
cur_mod / cur-module hint).
747_def_modqual_modshadow: table-driven sentinel — gamma calls
alpha.MSG with beta.MSG (same-leaf-name) at head of c.defs/sdefs.
want_imm "$38," (alpha strlit len), bad_imm "$27," (beta strlit len),
plus cs-vs-ws byte-id. Reverting cstage walk #2 to head-pick → fails
$38 on cstage + diverges cs-vs-ws; reverting wwstage cgdot to plain
deflookuprhs → fails $38 on wwstage.
make test 121/121; ww2==ww3==ww4 byte-id holds.
Frozen-artifact catch-up. 5466ea0 modified lib/strings/strings.ww and
lib/strings/stringstest.ww but did not regenerate the three bundled
.combined.ww files. Bisect of the frozen-fallback build path was
broken at 5466ea0..HEAD.
concat(a, b: str) -> concat(strs: str...) per ref/hare/strings/concat.ha:5.
Drop nomem return per project no-alloc-error idiom (os.alloc aborts).
Unblocked by #16 variadic-pack store fix (3bd9b1d).
concat_cases rewritten to table-driven: flat pool + argo/argn parallel
arrays + slice-spread call. 9 rows cover Hare concat.ha:18 vectors
(0/1/2/3-arg, multibyte) plus empty-mid/first/last/2-empty edges.
Bisect via signalled = 200 + i.
trim/contains variadic held on task #36 — surfaced by worker-variadic
pre-flight: iter + match prev composition in non-leaf callees still
hits scanlocals offset divergence. Resolves via #15 size-strategy.
make test 121/121; ww2==ww3==ww4 byte-id holds.
Class A silent miscompile. wwstage cgenexpr.ww cgident's bare-ident
deflookup→true branch and cgdot's module-qualified leaf branch
emitted `MOVQ <mod>.<name>(SB), AX` for a `def MSG: str = "..."`
value reference — a load from a SB symbol that emit_data never
writes. Str defs are not laid out at SB; they live as interned
strlits the .ptr/.len fold (post-#4c) and value-load consume.
Cstage already strlit-inlines via Sdef walks #1 (case N_IDENT
non-local) and #2 (case N_DOT untyped-lhs); wwstage now matches
the (LEAQ _S_<n>(SB), MOVQ $<len>, BX) emit shape per rule 10.
Surfaced by reviewer-def during #4c R3 while attempting option (B)
for the cstage Sdef walks #1/#2 prefer-pass — both walks'
cs-vs-ws byte-id sentinel rows could not pass while wwstage
emitted the bogus DATAW shape. Filed as #12 and deferred until
the wwstage emit shape was fixed. Unblocks #11 + #13 (cstage
prefer-pass graduations).
Latent: no in-tree corpus referenced a str def as a value (only
as .ptr/.len via cgdot field-fold) prior to lib/strings c3 —
same corpus-coverage-blind shape as the #4a-#4e graduations.
746_strdef_inline pins both sites with 2 rows: bare ident +
mod-qualified. Each row asserts `LEAQ _S_` + `MOVQ $<strlit_len>,`
inside the caller TEXT before RET, anti-checks the pre-fix
`<mod>.<name>(SB)` symbol-load, and cs-vs-ws byte-id per row.
120/120 ok. ww2 == ww3 == ww4 byte-id holds.
Class A silent miscompile, surfaced by landing strings.slice in
Hare's natural delegation form `fromutf8_unsafe(utf8.slice(begin,
end))` (ref/hare/strings/iter.ha:75). strings.slice itself returns
str, so the inner utf8.slice (cross-module N_DOT) call's cgcall
return-ABI fixup hit post-#4e fnretlookup's same-module-first walk
and grabbed strings.slice's own str return — emitted a spurious
`MOVQ DX, BX` after the cross-module CALL even though utf8.slice
returns []u8 (selfhost/cmd/wcc/cgenexpr.ww cgcall return-ABI fixup,
line 3249-3261 pre-fix). Every other consumer of cgcall:3249's
str-shuffle decision sat on the same bare-leaf table and was
silently miscompiling on the same collision shape pre-#34.
Sibling: nodeisslice + nodeisstr N_CALL arms in
selfhost/cmd/wcc/cgenutil.ww were N_IDENT-only — for a cross-
module N_DOT call returning a slice or str, pushargsrev fell
through to the natural 1-word PUSHQ AX, dropping the `.len`
(and `.cap` for slices) of the return value when consumed as a
call arg. strings.slice's body passes utf8.slice's []u8 result
to fromutf8_unsafe; pre-fix wwstage pushed 1 word vs cstage's
3, breaking the receiver's slice-3-pop drain.
Cstage carries no sister bug: cmd/w6c/cgen.c reads return shape
from the typed `n->lhs->type` (TY_FN sig) for both str-shuffle
and slice-/str-arg push counts — module-aware via the typed AST,
sidestepping any bare-leaf table. Mirror of #4e's cstage-no-
sister-bug note.
Fix: route cgcall return-ABI fixup + nodeisslice/nodeisstr N_CALL
arms through fnretlookupmod with `callee.lhs.str` (N_DOT
qualifier) or `c.curmod` (N_IDENT). Mirror of #28
fnparamslookupmod / #31 fnretlookupmod N_DOT re-routing.
Remaining bare-leaf fnretlookup consumer sites (~8 sites across
cgenexpr/cgenutil/cgenstmt/cgendecl listed in task #34a) stay
on the graduated bare-leaf path — none of the present-corpus
N_DOT leaf collisions have return-shape divergence at those
sites. A future stdlib port introducing a return-shape-divergent
same-leaf N_DOT collision will need the *mod re-routing — filed
as #34a sibling-latents.
Bundled three concerns per rule 11: cgcall fix, nodeisslice/
nodeisstr fix, and strings.slice retire + sentinel. (a) alone
leaves strings.slice byte-id breaking on slice-arg push count.
(b) alone leaves a phantom MOVQ DX, BX on the inner cross-
module CALL. (c) alone fails 995_self_rebuild without (a)+(b).
The three cannot land separately bisect-cleanly; the 745
sentinel pins the primary repro (cgcall str-shuffle) which
sentinel-flips on a cgcall:3257 revert.
745_fnret34_modshadow pins the fix with 1 row: caller.slice
returns str (same leaf as the cross-module callee, divergent
return shape); caller.run calls myutf8.slice returning []u8.
Asserts CALL myutf8.slice present inside caller.run TEXT +
`MOVQ DX, BX` anti-check on each stage plus cs-vs-ws byte-id.
strings.slice retired in lib/strings/strings.ww: the deferral
block becomes the natural Hare delegation form with two local
utf8.decoder reconstructions for the iterator endpoints — ww
has no anonymous-embed (parallel to the existing `move` helper).
iter_slice_cases mirrors ref/hare/strings/iter.ha:110-127;
sidesteps the Hare `let t = s;` iterator-copy via fresh
strings.iter() to stay clear of #35's sibling latents.
119/119 ok. ww2 == ww3 == ww4 byte-id holds.
let p2: T = p1; where T is a struct >8B and rhs is a local ident
silently dropped most of the copy. Cstage's N_LET fell past every
specialized rhs branch (str/tuple/tagged/structlit/call) without
matching the bare-ident case, then past the sz==8 fallback (false)
to the no-rhs zero-init (false: rhs present), emitting zero
instructions — the dest slot read fresh-stack zeros. Wwstage's
cglet fell to cgexpr+MOVQ AX which loads only the first qword
(cgident shape for struct ident), and for sz==16 slots the
str-init tail then stored a stale BX into +8. Reads after the
let saw whatever the stack held: silent partial copy.
Both stages now byte-copy src slot → dst slot per qword with
a sized tail (MOVL/MOVB) for natural sizes not 8-aligned.
Mirrors cg_widen_tagged_store's struct-ident payload copy.
744_letcopy_struct pins the four struct shapes (3×i32, i32+str,
i32+[]u8, i32+tagged) on asm-presence in both stages, cmp -s
byte-id, and runtime exit code via both drivers.
Scope: only N_IDENT rhs at the local-ident-found path. Filed as
siblings (no in-tree consumer today, bootstrap byte-id proves it):
- N_DOT / N_INDEX / N_UN(deref) struct rhs.
- Top-level (non-local) struct ident rhs.
- TY_TUPLE same-shape ident-copy bug.
Row (a) uses tri{a=11, b=22, c=33} structlit init for p1 to
isolate this fix from STATUS-3 #15/#26c (no-rhs zero-init sz=12
vs sz=16 slot-padded divergence between stages, separate task).
Row (d) runtime check uses only p2.a to isolate from match-on-
tagged-field scrutinee spill divergence (same task).
118/118 ok. ww2 == ww3 == ww4 byte-id holds.
Port four of the five c3 strings functions per ref/hare/strings/iter.ha;
strings.slice deferred behind task #34 (wwstage fnretlookup same-name
cross-module phantom return-ABI fixup, sub-bug of #4e).
- prev ref/hare/strings/iter.ha:49
- riter ref/hare/strings/iter.ha:32
- iterstr ref/hare/strings/iter.ha:63
- position ref/hare/strings/iter.ha:82
Also adds a private move() helper (ref/hare/strings/iter.ha:51) shared
by next/prev. Hare's move picks the utf8 function via a fn-pointer
(`let fun = if (forward) &utf8::next else &utf8::prev`); ww has no
fn-pointers in scope yet, so move branches on `forward` and calls
utf8.next or utf8.prev directly at each site.
strings.next is updated to dispatch via move(!it.reverse, it) — c2's
implementation always called utf8.next regardless of iter.reverse,
which was correct for forward iter() but would walk forward on
riter()-produced iterators too. With riter landed in this commit,
next() now correctly walks backward on reverse iterators per Hare's
ref/hare/strings/iter.ha:45. No in-tree consumer regression: only
stringstest constructs iterators today.
strings.iterstr uses ww's `[lo:hi]` slice syntax instead of Hare's
`[lo..hi]`; same semantics (borrowed []u8 view).
strings.slice deferred — Hare's body is
`fromutf8_unsafe(utf8::slice(begin, end))` (ref/hare/strings/iter.ha:76).
That delegation form triggers a wwstage fnretlookup miscompile when
the caller module has a function of the same name as the callee
(here: both strings::slice and utf8::slice exist), causing wwstage
to emit the wrong return-ABI fixup (MOVQ DX, BX, str's AX/DX→AX/BX
shim) after the cross-module CALL. Cstage handles the collision
correctly; wwstage routes through the same-module function's
return type and the byte-id checks (993_ww_ww + 995_self_rebuild)
trip. Filed as task #34 with minimal repro; will land strings.slice
when the fnretlookup graduate-by-module sub-bug in #34 is fixed.
Top-of-file divergence note lists slice in the deferred set; the
landing site keeps a comment-only stub. The public strings c3
surface ships 4-of-5 in this commit; slice + #34 land together in
a follow-up.
Tests: 5 new @test fns in stringstest.ww (signalled 22-26):
iter_prev_at_start_cases (prev at offs=0 → done),
iter_prev_ascii_cases (round-trip on forward iter),
iter_full_cases (mirror of ref/hare/strings/iter.ha:84-108 — iter
"こんにちは" with mid-walk iterstr + prev + next, then s = riter(...)
sret-into-existing-slot for the reverse iterator pass),
iter_position_cases (position tracks offs through a multibyte walk),
iter_iterstr_reverse_cases (riter iterstr is bytes BEFORE the cursor,
dual to forward iter's bytes-AFTER).
The Hare @test fn iter body uses `s = riter("にちは")` mid-test to
swap the iterator's direction (ref/hare/strings/iter.ha:101); ww's
sret-into-existing-slot path handles that fine (probed pre-port).
struct-copy let-from-ident (task #32) is sidestepped because no
test creates a duplicate iterator via `let dup = it;`.
117/117 ok. 995_self_rebuild stays green (ww2==ww3==ww4 byte-id).
993_ww_ww + 994_w6c_ww also green (cstage/wwstage byte-identical
on every corpus input including selfhost/cmd/wwdump/main.combined.ww).
Port four deferred utf8 functions per c2 backlog (utf8.ww:18
pre-port). All are non-trivial enough that the test rows mirror
Hare's @test fn decode/slice bodies (ref/hare/encoding/utf8/
decode.ha:85-198) row-for-row.
- prev ref/hare/encoding/utf8/decode.ha:52-71
- remaining ref/hare/encoding/utf8/decode.ha:74
- slice ref/hare/encoding/utf8/decode.ha:80-83
- position ref/hare/encoding/utf8/decode.ha:203
prev walks back from d.offs to a byte that could start a codepoint
(state-0 dfa cell != -1), re-decodes forward from there, and
confirms the forward decode lands back at the original offset.
Returns done at start-of-input; invalid if no initial byte appears
within 4 steps (no legal UTF-8 codepoint exceeds 4 bytes) or if
the forward decode shortcircuits to more/invalid or lands at a
different offset than expected.
Two structural deltas from the Hare source:
- Hare's `for (d.offs < len(d.src); d.offs -= 1)` relies on
size_t wrap-around to exit when offs underflows past 0; ww's
offs is i32 (utf8.ww:204), so the same exit is spelled
`d.offs >= 0`.
- Hare's `defer d.offs = t` restores offs after the return; ww
has no defer, so the restore is inlined in each match arm.
slice asserts the Hare precondition (same source + begin.offs <=
end.offs) via abort; Hare uses assert(). position is a one-liner
returning d.offs (Hare uses size, ww uses i32 per lib/CLAUDE.md
"indices use the underlying length type").
The `bi: i32 = b: i32;` indirection in prev's dfa lookup is
required because `dfa[b: i32]` parses as a slice expression
`dfa[b : i32]` where `i32` becomes the upper bound. The let-binding
matches the existing pattern at utf8.ww:236-238 in the c1 next()
port.
Tests: 14 new @test fns in utf8test.ww (signalled 22-35):
prev_done_at_start, prev_one/two/three/four_byte (round-trip
forward+reverse), prev_mixed_roundtrip (full forward then full
reverse on the same こんにちは+NUL input Hare uses at
decode.ha:85-111), prev_continuation_only_more (Hare's
[0xA0,0xA1] more case at decode.ha:117), prev_incomplete /
surrogate / overlong / extracont_invalid (decode.ha:120-150),
prev_max_in_range (decode.ha:158-163; pins state-7 acceptance via
reverse decode), prev_min_out_of_range (decode.ha:166-169; the
only case that trips prev's 4-step-bound arm), and
remaining_slice_position mirroring decode.ha:172-198.
The Hare slice @test idiom `let d2 = d1` (struct copy) miscompiles
in both stages (cstage + wwstage zero-init the rhs instead of
copying — task #32, Class A but bootstrap-byte-id-symmetric, so
995 doesn't catch it). The ww test uses two parallel
`decode(src[0:16])` calls to produce two decoders with the same
src.ptr; coverage on slice() is equivalent (exercises the same
source-different-offs pattern). Divergence cited inline.
117/117 ok. 995_self_rebuild stays green (ww2==ww3==ww4 byte-id).
cstage variadic gather stored only AX (.ptr) per element; .len and
.cap read stack residue at the callee. Tagged-union variadic path
escaped because cg_widen_tagged_store wrote the full slot — but
primitive-type variadics (str..., slice...) silently dropped the
trailing fields. Selfhost only uses tagged-union variadics
(formattable...) so bootstrap byte-id ww2==ww3==ww4 stayed green;
the bug surfaced in worker-strings pre-flight (session 5) on the
Hare-faithful concat(strs: str...) shape.
Per-element store branch now mirrors selfhost/cmd/wcc/cgenexpr.ww
velemstr (AX→slot+0, BX→slot+8) and velemslice (AX→slot+0,
BX→slot+8, CX→slot+16). Also swap dname-before-sname allocation
order in the variadic-pack frame layout to match wwstage scanlocals
+ localadd order (cgendecl.ww:507-516 and cgenexpr.ww:2949-2954);
without the swap post-fix asm has correct stores at mismatched
offsets vs wwstage.
Rule-10 alignment: cstage UP to wwstage's already-correct primitive
variadic path.
743_variadic_pack pins the contract: asm-presence ≥3 ptr-stores +
≥3 len-stores in caller TEXT on both stages, plus cs-vs-ws cmp -s
byte-id per row. 117/117 ok. Bootstrap byte-id ww2==ww3==ww4 holds.
Unblocks: lib/bytes contains-variadic, lib/strings sub variadic,
and the concat/trim/contains family that c1 shipped non-variadic.
Wwstage w6c_ww silently exited 0 on parse errors (stderr noise
only). The driver ran cgen on the broken AST then only checked
l.errs; ps.errs was never read, so callers downstream
(`ww build`, make rules) saw no signal and proceeded with junk
asm. Cstage cmd/w6c/main.c gates on `l.errs || p.errs` before
cgen; mirror that, hoisting the check above cgfile so the broken
AST never reaches codegen.
New test 742_parse_error pins the contract on both binaries:
writes a known-bad fragment to a pid-scoped /tmp file, runs cstage
w6c unconditionally and wwstage w6c_ww if available, asserts both
exit non-zero. Pre-fix wwstage exited 0 with junk asm; post-fix
exits 1 with parse: messages preserved on stderr.
116/116 ok. ww2 == ww3 == ww4 byte-id holds (no behavior change
for valid input).
The five $(BIN)/*_ww rules all built via `cd $(BIN) && ./ww build ...
; mv $(BIN)/main $@`. The ww driver writes the linker output to
<cwd>/<basename(src)> and has no -o flag, so every wwstage rule
landed on out/bin/main before its mv. Under `make -j8` the writes
and renames interleaved, leaving w6c_ww with a wwdump_ww (or other)
payload — silent under -j because the mv usually succeeded against
whatever `main` happened to exist at that instant. Symptom downstream:
test runs failing with `wwdump: cannot open -o`, recovered only by
falling back to -j1.
Build each rule in its own $(BIN)/<target>.d/ so the shared `main`
name is per-target. Switch -I and source args to $(CURDIR)/...
absolute paths and invoke ww by absolute path so the driver's
self_dir-relative libwwrt.a lookup still resolves to out/lib.
Side files (.combined.ww/.s/.o) land next to source via the parser's
source-path stem derivation, not cwd — unaffected. nocc target has
similar shape but its 4 builds are sequential recipe lines inside
one target so make -j can't parallelize them; not at risk today.
115/115 ok under both -j8 and -j1 from clean. ww2 == ww3 == ww4
byte-id holds.
Wwstage dirfilekeep checked only the first 5 chars of ".combined.ww"
(.comb), leaving a latent over-filter for hypothetical filenames of
shape .combXXXX.ww. Cstage enumerate_dir_ww in cmd/ww/main.c uses
strcmp on the full 12-char tail; mirror that here per rule-10
symmetric-stages. Extends the nested-if cascade to also gate on
'i','n','e','d' at offsets nlen-7..nlen-4; the trailing .ww is
already enforced by the function's leading early-out, so re-checking
those three positions would be dead and is called out in the comment.
No corpus trigger today; bootstrap ww2==ww3==ww4 byte-id holds.
Predecessor: #22 dir-enum (9e0816e) introduced the predicate.
115/115 ok. ww2 == ww3 == ww4 byte-id.
Wwstage's N_INDEX-lhs cgassign dispatch chain had a triple-site
N_DOT base gap (sister latents filed during #24 / #27 review):
Read (#28): `obj.mat[i][k]` over a struct field mat: **u8.
cgindex routes the outer N_INDEX's N_INDEX base through
indexvaluetnode; the recursion bottomed out at the inner
N_INDEX's N_DOT base with bt=nil. esz fell through to 8 +
signed_elem to false — wwstage emitted a stray outer
`MOVQ $8, CX; IMULQ CX, AX` plus `MOVQ (AX), AX` (8-byte
read over a 1-byte u8) instead of cstage's bare
`MOVZBQ (AX), AX`.
Write (#30): `obj.arr[i] = v` over a struct field arr:
[N]Tagged (e.g. (i64|str)). cgassign's N_DOT-base arm
computed esz via indexbaseesz but never set elemtn, so the
tagged-element store gate missed and the 24-byte tagged slot
was overwritten by a single scalar MOVQ — wrong-width store
+ tag/payload junk in the upper 16 bytes.
Cstage walks `n->lhs->type` directly via the typed AST
(cmd/w6c/cgen.c idx_eff + the N_INDEX-lhs N_ASSIGN branch).
Wwstage now mirrors via indexvaluetnode, which #24 (aa8ca47)
introduced for the N_INDEX-base case; #28/#30 graduate it for
N_DOT base via the existing dotfieldtnode helper.
Bundle graduates N_DOT base for the entire N_INDEX-lhs cgassign
chain: (a) indexvaluetnode in cgenutil.ww handles N_DOT base via
dotfieldtnode; (b) cgassign N_DOT-base arm in cgenexpr.ww calls
indexvaluetnode for elemtn; (c) scanlocals N_DOT-base arm in
cgendecl.ww parallels the existing N_IDENT arm for tagscr-bump.
Splits are bisect-incoherent: (b)-alone clobbers locals via
under-sized frame, (a)-alone leaves the write path with wrong
elemtn, (c)-alone has no consumer. Only the triple delivers a
complete N_DOT-base graduation matching #24's N_INDEX-base
pattern.
Cstage's first-use+fail-loud strategy for @tagscr (#26 commit
069548d) handles the N_DOT-base shape naturally; the scanlocals
N_DOT arm is wwstage-specific. Long-term rule-10 convergence
(wwstage DOWN from scanlocals to first-use+fail-loud on BOTH
stages) is filed as task #15.
Class A wwstage cgen UNDER. No in-tree consumer; sister latents
filed during #24 + #27 reviews. Test 741_dotbase_chained pins
the dispatch + cstage-byte-identical asm for both rows.
Sister latent (filed): indexbaseesz has no N_TARRAY arm for
scalar struct-field array writes — `s.arr: [N]i32` scalar write
falls through to esz=8 on wwstage. No in-tree exerciser; tight
scope kept here.
115/115 ok. ww2 == ww3 == ww4 byte-id.
Wwstage cgassign's N_INDEX-lhs base-inspection (cgenexpr.ww) only
computed esz/elemtn when base.kind == N_IDENT or N_DOT. For a
chained `names[i][k] = v` (names: **u8) the outer N_INDEX has
base.kind == N_INDEX; esz fell through to the default 8 so the
outer store emitted `MOVQ AX, (BX)` into a 1-byte u8 slot (8 bytes
written — adjacent memory corrupted) plus a stray
`MOVQ $8, CX; IMULQ CX, AX` scaling on the outer index that cstage
doesn't emit. Wrong-width-store: the byte slot was written as 8
bytes and the outer offset multiplied by sizeof *u8 instead of
sizeof u8.
Cstage walks `n->lhs->type` directly via the typed AST at the
N_ASSIGN N_INDEX-lhs branch (cmd/w6c/cgen.c eff->sub->size = 1).
Wwstage now mirrors via indexvaluetnode (already graduated for
cgindex in #24, commit aa8ca47) — the cgassign N_INDEX-lhs branch
gains the parallel base-N_INDEX arm: call indexvaluetnode, then
elemsizeofc for esz and one-layer-strip for elemtn (so the tagged-
element gate keys honestly on the element type, matching the
N_IDENT branch's pattern).
Class A wwstage cgen UNDER. Sister latent of #24's surfaced read-
path bug; filed during the #24 graduation with selfhost + lib grep
empty for chained-write. No in-tree consumer surfaced this before
the fix, so test 740_chained_write is the sole exerciser — pins
cstage-byte-identical asm for **u8 (MOVB store, 1 inner-stride-8
IMULQ pair, no outer scale) + **i32 (MOVL store, inner $8 + outer
$4 IMULQ pairs). Anti-check on the u8 row guards against the pre-
fix stray `MOVQ AX, (BX)` regression.
Sister latents filed (no in-tree consumer):
cgassign N_DOT-base elemtn drop (sister of cgindex N_DOT-base
in #24 review): tagged-element store via obj.arr[i] over a
struct-field array falls through to scalar store.
114/114 ok. ww2 == ww3 == ww4 byte-id.
Wwstage cgindex's base-inspection (cgenexpr.ww) only computed esz/
signed_elem when base.kind == N_IDENT or N_DOT. For a chained
`names[i][k]` (names: **u8) the outer N_INDEX has base.kind ==
N_INDEX; esz fell through to the default 8 so the outer load
emitted `MOVQ (AX), AX` over a 1-byte u8 plus a stray
`MOVQ $8, CX; IMULQ CX, AX` scaling on the outer index that cstage
doesn't emit. Wrong-width-narrow-load: the byte was read as 8 bytes
(reaching into adjacent memory) and the outer offset multiplied by
sizeof *u8 instead of sizeof u8.
Cstage walks n->lhs->type directly via the typed AST
(cmd/w6c/cgen.c idx_eff → eff->sub->size at N_INDEX). Wwstage
needed the parallel via indexvaluetnode — return the value-type
of an N_INDEX expression by stripping one element layer off base's
type, recursing for chained inner. cgindex's else-if chain now
adds the N_INDEX arm: call indexvaluetnode + elemsizeofc/
elemissignedc.
Class A wwstage cgen UNDER. Surfaced first time the codebase
exercised the **T[i][k] shape — through expanddir in
selfhost/cmd/ww/main.ww (post-#22 dir-enum, commit 9e0816e). The
workaround there split names[i][k] into `let nm: *u8 = names[i];
nm[k]` to route through the bare-pointer index path. Retired in
this commit: expanddir uses the natural chained form since the
read path is now byte-identical across stages.
Bundling justification (rule 11): the workaround retirement is
the in-tree verification this fix works — without retiring,
neither bootstrap byte-id nor 995_self_rebuild exercises the
chained read shape. Test 739_chained_index pins cstage-byte-
identical asm for **u8 (MOVZBQ load, 1 inner-stride-8 IMULQ pair,
no outer scale) + **i32 (MOVSXD load, inner $8 + outer $4 IMULQ
pairs).
Sister latents filed (no in-tree consumer, no probe):
Task #27 — cgassign chained-write N_INDEX: write path
`names[i][k] = v` for **u8 has the same dispatch gap. Selfhost +
lib grep is empty.
New latent (filed during review) — cgindex N_DOT base on chained
index: `obj.mat[i][k]` over a struct-field base falls back to
esz=8. indexvaluetnode currently handles N_IDENT + N_INDEX bases
only.
113/113 ok. ww2 == ww3 == ww4 byte-id.
Replace the cmd/ww + selfhost driver's file-walk import resolver
with true directory enumeration. `import encoding.utf8;` now finds
the lib/encoding/utf8/ directory and concatenates every *.ww file
in it (excluding *test.ww and the driver's *.combined.ww artifacts)
in byte-wise sorted order, instead of just finding the single
lib/encoding/utf8/utf8.ww file. Mirrors Hare's
hare/module/srcs.ha:183 _findsrcs minus tag handling.
Lookup order in both stages: (1) <dir>/<dot-as-slash>/ as directory
→ enumerate. (2) <dir>/<dot-as-slash>.ww as file. The legacy
<dir>/<name>/<name>.ww shape from #18's retained divergence is
dropped per rule-9 Hare-fidelity — Hare has no foo/foo.ha fallback;
a module IS the directory.
Symmetric across cstage (cmd/ww/main.c via opendir+qsort+stat) and
wwstage (selfhost/cmd/ww/main.ww via existing lib/os.getdents64 +
os.stat — no new lib/os surface needed; the rundirtests() walker
in main.ww from #18 was the model). Bootstrap ww2.s==ww3.s==ww4.s
byte-identical post-change.
Bundling justification (rule 11): strict-same-package validation is
bundled because the failure mode is dir-enum's own (a non-dir-enum
compilation unit cannot trigger mismatch across enumerated files).
The natural enforcement site is the driver — the parser can't
distinguish dir-enum concat from file-walk concat. Both stages
peek each file's first `package <name>;` line in expand_dir /
expanddir and exit(1) on mismatch with a precise error pointing
at the offending file. Hare's hare/module/srcs.ha:131 has the
same constraint via its README gate. Other half of #23 (strict
missing-package error tightening — 63 inline-source test wrappers
blocker) stays deferred per its filing.
Parser side (cmd/wcc/parse.c parseuse + lib/ww/parse/decl.ww
parseuse): n->str now carries only the LEAF identifier from a
dotted import. With the driver translating the full dotted path
to a directory walk, the checker only needs the package bareword
(last component) for the N_USE → decl disambiguation walk in
check.c's src_imports / decl_mod. Mirrors Hare's
`use encoding::utf8;` → `utf8::name` semantics
(ref/hare/hare/ast/import.ha:7).
Migration: lib/ww/sym.ww drops `import typ; import ast;`;
lib/ww/parse/parse.ww drops `import expr; import stmt; import
decl;`; lib/ww/lex/lex.ww drops `import tok;` — all sibling
imports auto-resolve via the new dir-enum when callers import the
package directory. lib/strings/, lib/encoding/utf8/utf8test.ww
migrate `import utf8;` → `import encoding.utf8;`. Makefile drops
-I lib/encoding/utf8 stopgap from wwdump_ww + w6c_ww. Seven test
wrappers (700_e2e, 966_strings_run, 970_fmt_run, 971_log_run,
972_fnmatch_run, 982_getopt_run, 990_selfhost) and 995_self_rebuild
drop the -I lib/encoding/utf8 runtime stopgap.
Tests: new 737_direnum C wrapper + test/wcc/data/direnum/ fixtures
pin (a) cross-pkg multi-file dir-enum build at runtime (both stages
must succeed) and (b) strict-same-package mismatch error (both
stages must surface "differs from" + exit non-zero). 738_module_decl
gains row 6 pinning the n_use->str leaf-only storage post-parser
change.
Retained workaround at selfhost/cmd/ww/main.ww expanddir loop:
`names[i][k]` nested-deref-then-index split into
`let nm: *u8 = names[i]; nm[k]` because wwstage cgen miscompiles
the chained form (treats inner u8 element as 8B sizeof *u8 instead
of 1B sizeof u8: extra MOVQ $8 + IMULQ on the inner index, MOVQ
instead of MOVZBQ load). Inline rule-8 WHY comment cites task #24
(wwstage cgen chained-index inner element size on **T). Two-step
form routes through the bare-pointer index path which both stages
handle byte-identically.
Class A wwstage cgen UNDER (chained-index inner element size on
**T) surfaced first time the codebase exercises the **T[i][k]
shape via enumeratedir() — corpus-coverage-blind landmine pattern,
same family as the trio (#27/#28/#31) from STATUS-5.
112/112 ok. ww2 == ww3 == ww4 byte-id holds.
User-mandated language redesign: source files declare their own
namespace via the new `package <name>;` keyword and pull dependencies
via `import <path>;`. Both keywords use Plan-9 `.` separator (user
override on Hare's `::` — `import encoding.utf8;`). Internal token-
kind enum values TK_MODULE=86 and TK_USE=17 kept stable for 990
wwdump byte-diff symmetry; only kwtab strings + tokname spellings
rotated. Executables (selfhost/cmd/{ww,w6c,w6a,w6l,wwdump}/main.ww)
declare `package main;` per Go convention; lib/ + selfhost/cmd/wcc/
files declare their parent-dir basename.
One-commit bundle per the brief's all-at-once directive: a per-stage
split breaks bootstrap byte-id mid-rewrite (cstage with new keyword
can't parse old `module`/`use` files and vice-versa). Body documents
the bundle per rule 11.
Two retained divergences from the user's stated ask, both filed per
rule 7 / rule 8 with inline task pointers at the deferred sites:
Task #22 — Directory-as-module enumeration in the driver. User
asked: "module is combination of files in directory" (golang/hare
shape). After this commit lib/ww/{ast,sym,typ}.ww all declare
`package ww;` but are still pulled into the compilation unit via
explicit sibling `import` chains (sym.ww does `import ast;` etc.),
not via dir enumeration. The cstage scaffold for true dir
enumeration was drafted and reverted because the symmetric wwstage
port requires a ww-side opendir/readdir wrapper around getdents64
(~150-200 lines new ww). Inline citation at locate_import_in /
locatein in both stages points to task #22.
Task #23 — Parser strict missing-`package` error. The original
brief mandated: parser errors when a .ww source omits `package
<name>;` as its first non-comment item. Softened here to silent-
default because 63 test wrappers (200_parse, 100_lex, 300_check,
400_w6c, ..., the inline-source-fragment family) build ad-hoc ww
source strings that lack `package` and the strict error cascaded
into 60+ test failures. Migration is mechanical-sed but deferred
so this commit ships green. Inline citation at parsefile in both
stages points to task #23.
Node.module renamed to Node.nmod and modent.module to modent.nmod
in wwstage source — the field name `module` would collide with the
freshly-reserved TK_MODULE token. The rename is left in place as
clean separator between AST-field-name and reserved-keyword
namespaces. Cstage's n->module retained — C has no `package` or
`module` keyword.
rt/ensure.ww deliberately ships WITHOUT a package declaration so
its `export fn rt_ensure` keeps the bare linker symbol; adding
`package rt;` would mangle to `rt.rt_ensure` and break libwwrt.a
linkage. Documented at the file head.
111/111 ok (110 + new 738_module_decl sentinel). 995_self_rebuild
byte-id holds (ww2 == ww3 == ww4). All 5 frozen
selfhost/cmd/*/main.combined.ww regenerated under the new driver.
CLAUDE.md rule 5 amended with the language-layer divergence note.
Class A frame-layout landmine pre-located; #26c queued for size-
strategy convergence per rule 10.
Cstage's tagged-scratch sites previously stamped per-call labels
via mklabel "tagbase"/"tagscr"/"argscr"/"idxscr", bumping labelseq
once per call and allocating a fresh frame slot. Wwstage routes
the same sites through localadd("@tagbase", ...) and
localadd("@tagscr", c.tagscrsz, nil) — the @-dedup shares ONE
slot per name per fn and never touches labelseq. @tagscr is
shared across THREE wwstage sites: cgenutil.ww:180 pushargsrev
struct-payload widen, cgenutil.ww:2918 cgwidentaggedstore
via_outer, cgenexpr.ww:3524 cgindex tagged-element. Worker's
initial draft introduced cg_argscr / cg_idxscr as separate
cache vars — names that don't exist in wwstage. Per rob's rule-10
amendment those collapsed to a single cg_tagscr shared across
the 3 sites, matching wwstage's @tagscr SSoT exactly.
Cstage now caches two slots matching wwstage's namespace exactly:
cg_tagbase (8B base spill, 1 site at cgwidentaggedstore via_outer)
and cg_tagscr (sized scratch shared across the 3 sites above).
Eliminates per-call labelseq bumps and per-call frame churn.
Class A byte-id drift (silent corpus-coverage-blind landmine)
closed for the 1-name shape match. Model: STATUS-3 #15 commit
987391b routed @retscr through the same SSoT via cg_retscr;
this commit extends the carve-out to @tagbase and @tagscr.
Size strategy: cstage has no scanlocals pre-pass (wwstage's
c.tagscrsz pre-pass at cgendecl.ww:32 tagscrbump computes the
per-fn max). First call across the 3 @tagscr sites sizes the
slot; subsequent calls reuse if sz <= cached, fatal() if larger
(rule 7: surface-don't-silently-corrupt). Long-term rule-10
convergence — wwstage DOWN from scanlocals to first-use+fail-loud
on BOTH stages (per rob: aligning richer DOWN to leaner) — is
filed as #26c, separate concern from #26's name-SSoT graduation.
Tests:
- 736_cstage_label_ssot succ_rows: pins cstage-vs-wwstage cmp -s
byte-id on the canonical pointer-rooted two-tagged-store shape
(two `c.v = (...: bag);` writes through *cell). Pre-fix cstage
frame was 16B+48B larger (2*@tagbase + 2*@tagscr per call);
post-fix single-slot SSoT matches wwstage byte-for-byte.
- 736_cstage_label_ssot fail_rows: pre-locates the size-grow
landmine. A fn with two unions of different slot sizes (16B
then 24B) routed through @tagscr; cstage must fatal() with
"@tagscr cached sz" + size mismatch + #26c follow-up cite.
Gates corpus growth into this shape against silent miscompile.
110/110 ok. 995_self_rebuild byte-id holds (ww2 == ww3 == ww4).
Class A silent miscompile, latent until two modules export the same
fn leaf name with diverging return-type categories (str vs scalar,
tagged vs not, tuple vs not, float vs int, struct-payload-size).
Wwstage's fnretlookup (selfhost/cmd/wcc/cgen.ww) walked c.fnrets
head-first by fname and returned the FIRST match's rtype. cgcall's
str-shuffle decision (cgenexpr.ww:3249) handed it calleename (the
bare leaf from an N_IDENT callee); a same-leaf foo registered later
(at head) returning str then mis-fired isstrtype(c, rt) for an
i64-returning callee, emitting a spurious MOVQ DX, BX after the
CALL — the SysV (AX, DX) → ww str (AX, BX) shuffle — corrupting
BX even though the callee never returned an str pair. Every other
bare-leaf consumer (taggedcallslot, callsretsize, exprfloatkind,
rhstaggedabicall, tuple destructure in cglet/cgmlet, fn-rvalue
LEAQ in cgident, cgtry{prop,unw} success-shuffle) keys on the same
fnretlookup return and was silently miscompiling under the same
collision shape.
Cstage carries no sister bug: cmd/wcc/check.c N_CALL routes
cexpr(c, n->lhs) through scope_lookup_prefer for an N_IDENT callee,
then cmd/w6c/cgen.c reads the return type from the typed
n->lhs->type's TY_FN sig — module-aware via the typed AST,
sidestepping any bare-leaf table. cs vs ws diverged on every same-
leaf fn return-category collision but no in-tree corpus declares
two same-leaf fns with diverging return categories today: 995
stays green (same surfacing pattern as #4a enumlookup post-strings,
#4b structlookup, #4c def, #4d fnparams).
Eighth and FINAL leaf of the trio graduation (after #27 aliaslookup,
#28 fnparams *mod*-variant, #31 fnret *mod*-variant, #4a enum, #4b
struct, #4c def, #4d fnparams bare-leaf). fnretlookupmod (the N_DOT
consumer at cgen.ww:1585) already exists post-#31; this commit
graduates only the BARE-LEAF entry point with a same-module-first
walk mirroring fnparamslookup's two-pass shape (#4d). 12+ bare-leaf
callsites consume the graduated lookup uniformly — none separately
re-routed to fnretlookupmod since the in-tree N_DOT collisions
(strings.next vs utf8.next; bytes.hasprefix vs strings.hasprefix
and equivalents) all have invariant return shape across the
colliding overloads. A future stdlib port introducing a return-
category-divergent same-leaf N_DOT collision will need the *mod
re-routing — file at that surfacing.
Pre-flight on 995_self_rebuild green: rob's brief warned 1-2 byte-
id surfaces possible because bare-leaf graduation could flip
MOVQ↔MOVSXD or push-count on selfhost compile paths not routed
through *lookupmod. Audit confirms the corpus has bare-leaf same-
name fn pairs (compare in lib/strings vs lib/time; next in utf8
vs strings) but downstream consumer behavior is invariant under
both shapes — cross-module calls all go through N_DOT →
fnretlookupmod, not the bare-leaf path. Zero actual surfaces.
731_fnret_bare_leaf_shadow pins the fix with 1 row: alpha defines
fn foo() i64 + fn alphacaller() i64 = { return foo(); }, beta
defines fn foo() str declared LAST in source so beta.foo prepends
to the head of c.fnrets. alphacaller's bare foo() must compile
against alpha.foo's i64 return (no str-shuffle) even with beta.foo
at the head of c.fnrets. Asserts CALL alpha.foo inside the right
TEXT sym + bad_imm MOVQ DX, BX anti-check on each stage plus
cs-vs-ws byte-id per row.
Class A silent miscompile, latent until two modules export the same
fn leaf name with diverging tagged-vs-scalar param shapes. Wwstage's
fnparamslookup (selfhost/cmd/wcc/cgen.ww) walked c.fnrets head-first
by fname and returned the FIRST match's params. cgcall's N_IDENT
branch (cgenexpr.ww:2875) handed it the bare leaf; pushargsrev's
istaggedtype(c, pt) then fired against the wrong-module foo's
param-type. A foo(7) call against a same-leaf (i32 | void) param
re-laid the i32 arg into a 2-word tagged slot (MOVQ $7 push + MOVQ
$0 tag push + 2 POPs into DI/SI) instead of the caller-intended
single push (MOVQ $7 push + POPQ DI).
Cstage carries no sister bug: cmd/wcc/check.c N_CALL routes
cexpr(c, n->lhs) through scope_lookup_prefer for an N_IDENT callee,
then cmd/w6c/cgen.c reads params from the typed n->lhs->type's
TY_FN sig — module-aware via typed AST, sidestepping any bare-leaf
table. cs vs ws diverged on every same-leaf fn collision but no
in-tree corpus declares two same-leaf fns with diverging tagged-vs-
scalar param shapes (same surfacing pattern as #4a enumlookup
post-strings, #4b structlookup, #4c def): 995 stays green.
Seventh leaf of the trio graduation (after #27 aliaslookup, #28
fnparams *mod*-variant, #31 fnret *mod*-variant, #4a enum, #4b
struct, #4c def). fnparamslookupmod (the N_DOT consumer at
cgenexpr.ww:2876) already exists post-#28; this commit graduates
only the BARE-LEAF entry point with a same-module-first walk
mirroring aliaslookup's two-pass shape (cgen.ww:75). Three bare-
leaf callsites consume the graduated lookup uniformly: cgcall
N_IDENT branch at cgenexpr.ww:2875 (load-bearing for the tagged-
widening shape), cglocalsize scratch reservation at cgendecl.ww:420
(fires only on tagged-param + struct-payload arg), and
callee_variadic_param at cgenutil.ww:66 (fires only on variadic
callee). The latter two also accept N_DOT callees and feed the
bare leaf — pre-graduation those head-picked, post-graduation
they prefer same-module. NOT separately re-routed to
fnparamslookupmod in this commit: the only in-tree N_DOT cross-
module fn collisions (strings.next vs utf8.next; bytes.hasprefix
vs strings.hasprefix and equivalents) all have invariant param
shape across the colliding overloads, so widening/scratch/variadic
behavior is invariant either way for sites 2 and 3 on the present
corpus. A future stdlib port introducing a tagged-vs-scalar or
variadic-vs-non-variadic same-leaf N_DOT collision shape will
need the *mod re-routing — file at that surfacing.
732_fnparams_bare_leaf_shadow pins the fix with 1 row: alpha
defines fn foo(x: i32) i32 and fn alphacaller() i32 = {
return foo(7); }, beta defines fn foo(x: (i32|void)) i32
declared LAST in source so beta.foo prepends to the head of
c.fnrets. alphacaller's bare foo(7) must compile against
alpha.foo's i32 param (single PUSHQ/POPQ DI shape) even with
beta.foo at the head of c.fnrets. Asserts the matching POPQ DI
inside the right TEXT sym + bad_imm POPQ SI anti-check on each
stage plus cs-vs-ws byte-id per row.
Class A silent miscompile, latent until two modules export the same
str-typed def leaf name and the .ptr/.len field-fold path consumes
the wrong-module strlit address/length. Wwstage's deflookuprhs
(selfhost/cmd/wcc/cgen.ww) walked c.defs head-first by dname; cgdot's
.ptr/.len field-fold handed it the bare leaf from N_IDENT.str,
silently inlining the wrong-module strlit. Cstage carries the same
shape at cmd/w6c/cgen.c (Sdef walk #3 N_DOT field-fold): Sdef keyed
by name only, head-pick on every cross-module collision. No in-tree
corpus declares two same-leaf str defs, so 995_self_rebuild stayed
green (same surfacing pattern as #4a enumlookup post-strings and
#4b structlookup).
Sixth leaf of the trio leaf-name lookup graduation (after #27
aliaslookup, #28 fnparams, #31 fnret, #4a enum, #4b struct). Same
bundle precedent as #4a (which bundled wwstage enumlookup +
enumlookupmod + cstage scope_lookup_prefer sister fix under one
structural concern): four sister changes ship together.
- defent +dmod field; collectdefs captures d.module.
- wwstage deflookup two-pass walk — cosmetic (bool return is
invariant under head-pick vs same-module-first), kept for
structural symmetry with deflookuprhs.
- wwstage deflookuprhs two-pass walk — load-bearing for the
.ptr/.len field fold.
- cstage Sdef +mod field; sdef_collect captures d->module raw
(matches cgfn's raw cur_mod convention); new sdef_mod_match
helper handles NULL-safe strcmp; cstage Sdef walk #3 N_DOT
field-fold graduation (sister of wwstage deflookuprhs).
Two additional cstage Sdef walks (N_IDENT bare load + N_DOT mod-
qualified fallback) are DEFERRED. Both consume wwstage's
cgenexpr.ww:553 path which is independently broken (str-def bare/
qualified reference emits MOVQ symname(SB) where strlit-inline is
required); sentinel rows for those walks fail cs-vs-ws byte-id
regardless of the cstage prefer-pass behavior. Per rule 7 the
prefer-pass cannot ship without sentinels. Filed: task #11 (cstage
walk #2 also needs n->lhs->str as hint source rather than cur_mod,
matching #4a/#28/#31's *mod variant pattern) + task #12 (wwstage
str-def symbol-load fix that unblocks both deferrals).
735_def_modshadow pins the fix with 1 row: bare-leaf .len of MSG
in module alpha must fold against alpha's own def MSG (strlit
length 41) even with beta's same-leaf 27-char def MSG at the head
of c.defs / sdefs. Asserts the matching immediate inside the right
TEXT sym + bad_imm anti-check on both stages plus byte-id between
stages.
Class A silent miscompile, latent until two modules export the same
struct leaf name. Wwstage's structlookup (selfhost/cmd/wcc/cgenutil.ww)
walked c.structs head-first by sname, returning the FIRST match.
cgdot's *struct field-load branch handed it inner.str (the bare
leaf from a parsed N_TPTR whose inner is N_TNAME) and the head-pick
silently emitted the wrong-module field offset — a displacement
against BX that loaded whatever the colliding-module struct happened
to align there. Cstage carries no sister bug: resolve_typename
(cmd/wcc/check.c:65) already routes bare-leaf TY_STRUCT names
through scope_lookup_prefer per c->cur_mod, and cgen.c reads
fi.foff off the typed Sym — cs vs ws asm diverged on every bare-
leaf collision but no in-tree corpus declares two same-leaf
structs, so 995_self_rebuild stayed green (same surfacing pattern
as #4a enumlookup post-strings).
Fifth leaf of the trio leaf-name lookup graduation (after #27
aliaslookup, #28/#31 fnparams/fnretlookupmod, #4a enumlookup):
structlookup grows a same-module-first walk before the head-walk
fallback, mirroring aliaslookup's two-pass shape. No structlookupmod
variant — pkg.S collapses at parse time (lib/ww/parse/parse.ww
joindotted) into a single N_TNAME str routed through the existing
embedded-dot smod==pkg branch, so there's no cgdot-style N_DOT
consumer surface to add a *mod variant for (deferred per rob until
one surfaces). No cstage symmetric fix needed for the same reason
the bug doesn't surface there.
734_struct_modshadow pins the fix with 2 rows: row 1 bare-leaf in
module M must fold against M's own S even with another module's
same-leaf S at the head of c.structs (asserts the matching field-
load disp inside the right TEXT sym + bad disp NOT-presence anti-
check + byte-id between stages); row 2 pkg-qualified alpha.S
from inside alpha is defensive coverage of the pre-existing
embedded-dot smod==pkg branch — same path pre/post-fix (no
sentinel-flip on this commit), pinned here so a future regression
to the embedded-dot lookup is caught.
Class A silent miscompile, latent until two modules export the same
enum leaf name. Wwstage's enumlookup (selfhost/cmd/wcc/cgen.ww)
walked c.enums head-first by ename; cgdot handed it the bare leaf
from N_DOT.lhs.str for both `Color.MEMBER` (lhs N_IDENT) and
`pkg.Color.MEMBER` (lhs N_DOT) shapes, silently dropping the
explicit qualifier on the second. Cstage's enum-member fold
(cmd/wcc/check.c cexpr N_DOT) was carrying the same head-pick on
the lhs-ident lookup — pre-fix the mismatch surfaced as a
"not assignable to <same-leaf>" checker error rather than a silent
wrong-constant because resolve_typename for the fn return spec
already used scope_lookup_prefer correctly, so the rhs's wrong-
module-Color clashed with the return type's right-module-Color.
No in-tree corpus currently declares two same-leaf enums, so
995_self_rebuild stayed green and the latent miscompile only
surfaces once a stdlib port introduces the collision (same shape
as #27 surfacing when lib/strings dragged utf8's invalid alias
into the chain alongside strconv's invalid).
Fourth leaf of the trio leaf-name lookup graduation (after #27
aliaslookup, #28 fnparamslookupmod, #31 fnretlookupmod): wwstage
enumlookup grows a same-module-first walk before the head-walk
fallback, mirroring aliaslookup's two-pass shape (cgen.ww:75).
The N_DOT consumer surface — `pkg.Enum.MEMBER`, already used
in-corpus by os.flag.RDONLY, temp.mode.RDWR, os.whence.SET etc.
— routes through a new enumlookupmod variant with the explicit
N_DOT.lhs.lhs.str as the mod qualifier (mirror of fnret/
fnparamslookupmod). Cstage's check.c cexpr N_DOT lhs lookup
graduates from scope_lookup to scope_lookup_prefer to align
symmetrically (rule 10: both stages pick same-module-first on
the bare-leaf shape).
733_enum_modshadow pins both surfaces with 3 rows: row 1 bare-leaf
in module M must fold against M's own Color even with another
module's same-leaf Color at the head of c.enums; row 2 same-module
`mod.Color.MEMBER` from inside that mod pins the API surface; row 3
cross-module `othermod.Color.MEMBER` from a third module with no
local Color sentinel-flips the cgdot etmod tracking + enumlookupmod
path independently of row 1's same-module-first fallback. Asserts
the matching \$N, immediate inside the right TEXT sym + bad_imm
NOT-presence anti-check on both stages plus byte-id between stages
per row.
Forward UTF-8 rune cursor per ref/hare/strings/iter.ha; iterator
flattens Hare's anon-embedded utf8::decoder to explicit
offs/src/reverse fields, next() copy-in/copy-out a local decoder
and aborts on more/invalid per move()'s discipline.
The iterator flattens Hare's anonymous-embedded utf8::decoder
(ref/hare/strings/iter.ha:6-9) to explicit offs/src/reverse
fields because ww has no anon-embed syntax. reverse is retained
on the struct so riter populates it once utf8.prev (reverse DFA)
and strings.prev land.
next() copies the iterator's offs/src into a local utf8.decoder,
delegates to utf8.next, then writes offs back; copy-in/copy-out
is the cost of the flattened layout. more/invalid arms abort with
"strings.next: invalid UTF-8", mirroring Hare's move()
(ref/hare/strings/iter.ha:51-58) which aborts unconditionally
on those arms.
Deferred surface (no in-tree caller; follow-up tasks): prev, riter,
iterstr, slice, position, move. prev specifically needs utf8.prev
(reverse DFA), which isn't on the lib/encoding/utf8 surface yet.
lib/strings/strings.ww moves off test/wcc/900_stdlib.c's
standalone-compile list per the existing bufio/fmt/os precedent:
the iterator's (rune | utf8.done) return type and the local
utf8.decoder reference need cross-module type resolution, which
the standalone w6c path doesn't do. Runtime coverage stays at
966_strings_run, which now exercises 21 signalled cases (was 15).
The iterator's Hare-faithful `reverse: bool` field surfaced #33
(cstage cgen narrow-sret-field copy mis-width) during this port's
pre-flight; that fix landed at 0d96196 ahead of this commit.
Future bisecters tracking a narrow-field-related regression in
lib/strings or sret-aware stdlib growth should consult #33 + this
commit's bracket. The 4-arm match on utf8.next return surfaced
#31 (wwstage fnretlookupmod) earlier in the same chain (b787641).
Tests:
- 6 new @test fns in stringstest.ww (signalled 16-21): empty,
ASCII, 2-byte (café), 3-byte (こんにちは), 4-byte (🦀rust),
mixed-width ("Hello, 世界! 🌍"). Each verifies forward
iteration, done@EOI, and repeated next-after-done stays done
(iter_empty). Multibyte literal limitation handled via
`0xE9u32: rune` cast per existing pattern at stringstest.ww:82.
104/104 ok. 995_self_rebuild stays green (ww2==ww3==ww4 byte-id).
Callee N_IDENT word-copy loop was driven off slot-padded rt->size;
trailing narrow field (e.g. bool@32 in 33B/40B struct) widened to
MOVQ at the loop tail, diverging from wwstage's natural-size MOVB.
Class A cgen divergence. 9th unmask of session 5, corpus-coverage-
blind on the cstage side — no in-tree lib struct had a narrow
(bool/u8/i8/i16) trailing field until lib/strings.iterator landed
`reverse: bool` per Hare's ref/hare/strings/iter.ha:8.
Pre-fix: cstage cgreturn's sret arm (cgen.c) used `int sz =
(int)rt->size` for its chained `while (k+8<=sz)` MOVQ-MOVL-MOVW-MOVB
copy loop. rt->size is slot-padded (8-rounded for downstream
frame alloc), e.g. 40B for {i32, []u8, bool}. Loop emitted MOVQ
at offset 32 covering the 1-byte bool tail plus 7 bytes of
padding into the caller's sret slot — clobbering the next 7 bytes
of caller frame on read-side. Wwstage's mirror loop drives off
sretretsize → structnaturalsize → max(foff+fsz) = 33B, so it
correctly stops at offset 32 and emits MOVB.
Polarity catalog: cstage OVER-WIDE — slot-padded size driving the
field-copy width. Convergence cstage → wwstage's structnaturalsize
discipline (rule 10 inverse: leaner-correct side wins).
Fix: compute natural size locally in the N_IDENT/N_STRUCTLIT sret
arm via walk over `rt->fields` (max foff+fsz), mirroring wwstage's
`structnaturalsize` (cgenutil.ww:1377). Frame allocation and
`cg_sret_retsize` (used for the caller-side @sretscr slot)
intentionally keep using rt->size — caller scratch sizing is
separate from callee per-field copy width.
Surfaced by lib/strings commit-2 (#30) iterator pre-flight when
the Hare-faithful `reverse: bool` field tripped the cstage-only
mis-width on 993/995 byte-id (strconv → strings → wwdump_ww +
w6c_ww). lib/strings c2 was stashed to land cleanly after this fix.
Note (out-of-scope): the chained MOV loop has no MOVW arm in
either stage, so a trailing i16 emits 2× MOVB at consecutive
offsets. Worth a future cleanup; both stages agree today.
Tests:
- 730_sret_narrow_field pins narrow-MOV store + load width and
no-MOVQ@trailing-offset assertions for bool / u8 / i16 / i32
trailing fields in a 33B-natural struct. 4 rows × 5 sentinels
= 20 fixtures. cmp -s cstage vs wwstage byte-id per row.
- 930_sret_narrow_field_run runtime-pins bool true/false, u8
high-bit, i16 negative, i32 negative, mixed (bool+i32+i64 after
slice) — 6 scenarios × 2 stages = 12 rows.
104/104 ok. 995_self_rebuild stays green (ww2==ww3==ww4 byte-id).
Wwstage matchscrutt now mirrors cstage's typed-AST scrutinee-type
lookup for module-qualified mod.fn(...) callees, restoring per-arm
tag dispatch on cross-module shadowed-name 4-arm matches. Class A
runtime miscompile, silent across collectfnrets shadowing — was
the 8th unmask of session 5.
Pre-fix: wwstage's matchscrutt N_DOT branch (cgenutil.ww:2061)
called `fnretlookup(c, callee.str)` — name-only resolution.
collectfnrets prepends to c.fnrets, so when a caller fn (e.g.
lib/strings's `next`) shadows a callee fn-name (utf8's `next`),
the prepend chain has the caller's narrower tagged return at the
head. matchscrutt then resolved the scrutinee type to the WRONG
tagged shape, and variantindex lookups for arms past the
shadowing caller's variant count returned -1 → want=0 →
match-arm `CMPQ $0, AX` for arms 2 and 3 on a (rune | done |
more | invalid) probe. Effect: arms 2/3 silently unreachable
even when the runtime tag matched, falling through to default.
Cstage gets the scrutinee type via the checker-set callee type
on the N_DOT node, so picks the correct utf8.next return shape.
Polarity catalog: wwstage UNDER — fnretlookup missing module-
preferring discipline. **Third leaf in the same trio**: #27
(aliaslookupmod), #28 (fnparamslookupmod), #31 (fnretlookupmod).
Pattern is recurring; full graduation of all leaf-name lookups
to same-module-first is a candidate for STATUS-3 task #1
variant-widen consolidation refactor (deferred to next session
opener per rob).
Fix: new fnretlookupmod helper in cgen.ww (same-module-first
walk, fallback to existing first-match — cell-for-cell mirror
of fnparamslookupmod from #28). matchscrutt N_DOT branch
extracts `cmod` from callee.lhs.str and routes through the
helper. Other 13 fnretlookup callsites untouched per #28's
"fix only what has a real consumer" discipline. fnret.fmod
field + collectfnrets f.fmod assignment already landed in #28.
Surfaced by lib/strings commit-2 pre-flight: probe iter+next
shape calls utf8.next; the probe's own `fn next` shadows
utf8.next at the c.fnrets head. Bootstrap-stable because no
selfhost-corpus path shadows a fn name across modules with a
wider tagged return on the shadowed side; lib/strings.iter
pulling utf8.next under wwstage was the first exerciser.
Filed follow-up (NOT in scope here): #32 wwstage runtime stomp
on utf8.next via *iterator caller — separate Class A surfaced
by 929 direct utf8.next regression row design. #31's fix is
correct in isolation; #32 blocks lib/strings commit 2 (#30).
Tests:
- 728_match_4arm_cross_module pins distinct CMPQ $K, AX tags
in TEXT b.next via bitmap covering [0..arms), robust to
arm ordering. Three cross-module shadowed-name shapes × cmp
-s byte-id. Sentinel-flip-verified: revert fnretlookupmod
route → 3/6 wwstage fixtures fail "arm K repeats tag $0
(collapse)".
- 929_match_4arm_cross_module_run runtime-pins 6 rows × 2
stages per-arm exit-code shape: 3/4/5/6-arm boundary,
mixed (i32|str|rune|u8), reverse arm-order in match source.
Confirms bug follows fnretlookup-resolved type, not match
source order.
102/102 ok. 995_self_rebuild stays green (ww2==ww3==ww4 byte-id).
