parseFnDecl now calls parseOptionalExternExport() after the callconv
slot and stores the modifier on FnDecl.extern_export. For 'extern' the
body is ';' (an empty-block placeholder — the modifier carries the
linkage, no *_expr node, per the naming constraint). Both fn-decl
lookahead predicates (isFunctionDef, hasFnBodyAfterArrow) now treat
kw_extern/kw_export as fn-body markers beside kw_callconv, so
'(...) -> R extern;' is recognized as a fn def rather than a fn-type
const.
Per user feedback, decision 4 ("library separate") is REVISED: extern
carries an optional LIB + "csym" axis mirroring '#foreign LIB "csym"',
so it is a true #foreign superset (Gate A->B requirement — the Part B
migration of 466 #foreign uses across 6 libs must preserve each
symbol's library). Added FnDecl.extern_lib/extern_name and
VarDecl.extern_lib (beside is_extern/extern_name).
All unconsumed by lowering: extern parses, but a fn still errors at
sema (body produces no value). Suite green (443 unit / 633 corpus).
lock commit.
Add ast.ExternExportModifier { none, extern_, export_ } beside
CallingConvention; FnDecl.extern_export and VarDecl.is_extern/extern_name
fields (all defaulting to absent); and Parser.parseOptionalExternExport()
mirroring parseOptionalCallConv.
None of this is consumed by a decl path yet — no user-facing behavior
change, corpus diff empty. Two inline parser unit tests pin the helper's
keyword mapping and the field defaults. Phase 1.0 wires the helper into
the fn-decl path. lock commit.
Lex 'extern' and 'export' as keywords beside 'callconv': new token.Tag
variants + keywords StaticStringMap entries + LSP semantic-token keyword
classification. Adds a 'lex linkage keywords' unit test.
Tokens only — parser/AST plumbing and lowering land in later phases.
Corpus sweep confirmed no .sx identifier collides with the new reserved
words. lock commit per the cadence rule.
Two new workstreams:
- ASM: inline assembly — asm { "tmpl", "=r" -> T, "r" = expr, clobbers(.…) },
multi-return tuples; lowers via the existing llvm_api.c (no shim).
- FFI-linkage: add extern/export postfix keywords, migrate every #foreign onto
them, then purge 'foreign' from the tree (end-state invariant).
Drop current/ from .gitignore so plans + checkpoints are tracked normally
(the dir was ignored; only checkpoints had been force-added). Includes
docs/inline-asm-design.md. specs.md change left uncommitted.
A tagged union (enum-with-payload) is laid out { tag, payload }, but a
direct member write `s.rect = payload` lowered to a payload-only store
(union_gep into field 1) with no tag store — the discriminant went stale,
so a later match/== took the wrong arm with no diagnostic (issue 0136).
The read path already distinguishes tagged unions (enum_payload/enum_tag);
the write path treated them like plain unions.
A variant is set via construction (`s = .variant(payload)`, which writes
both tag and payload). A direct member write can't safely set the tag (the
active variant isn't known at the write site), so it is now rejected with a
diagnostic pointing to construction. A new diagTaggedUnionVariantWrite guard
— reusing the shared fieldLvalueResolve matcher, applied at both store sites
(lowerAssignment, lowerMultiAssign) — fires only for a whole-variant write
on a tagged union. Plain `union` writes and nested sub-field writes
(`s.rect.w = ...`) are unaffected.
Resolves issue 0136. Tests: examples/0185 (rejected), 0186 (nested write +
construction still work). specs.md / readme.md updated.
Assigning a struct literal to a named-struct member of a plain union
(`u.b = .{ ... }`) lowered the RHS as .unresolved and tripped the
LLVM-emission tripwire: lowerAssignment's .field_access target-type
path used getStructFields, which returns nothing for a union, so the
literal never received its target type.
Unify the lvalue field matcher into a pure fieldLvalueResolve consumed
by both fieldLvaluePtr (GEP builder) and the target-type path, so the
store slot and the RHS target type can't diverge (covers union direct +
promoted members, tuple/vector lanes, and structs).
Resolves issue 0133 (depended on 0135). Regression test: examples/0184.
Notes the now end-to-end union path in issue 0132.
Erasing a single comptime-pack element to a protocol value
(`xx sources[0]` with a protocol target) tripped the pack-as-value
error: buildProtocolErasure treated the index_expr as an lvalue and
took its address via lowerExprAsPtr, whose .index_expr arm lowers the
bare pack as a value (a pack is comptime-only with no runtime storage).
isLvalueExpr now reports a comptime pack index as an rvalue, decided
via the same packArgNodeAt predicate the value path uses — so the value
and lvalue paths can't diverge on what counts as a pack element — and
erasure heap-copies the already-materialized element instead.
Resolves issue 0135. Regression tests: examples/0547, 0548.
`registerProtocolDecl` resolved each method's param/return type NAME
through the flat, visibility-unaware `type_bridge.resolveAstType`, so a
type name colliding across modules bound to the wrong author. In the
repro the user's `Event` enum collides with the stdlib `event.Event`
struct (pulled in by `modules/std.sx`): the protocol grabbed the stdlib
struct, typed an inferred `g_plat.one_event()` as a fieldless struct,
bound the `case .key_up:(e)` payload to `.unresolved`, and emitted
"enum literal '.escape' has no destination type to resolve against".
Resolve both param and return types through
`resolveTypeInSource(pd.source_file, …)` — the visibility-aware resolver
pinned to the protocol's own declaring module, keeping the `Self → *void`
short-circuit. Brings the non-parameterized path to parity with
`instantiateParamProtocol` and concrete-fn signatures. No silent default:
not-visible / ambiguous names still diagnose and poison with `.unresolved`.
Closes issue 0132 — the protocol-return case left open by f13f4ab (which
fixed the enum/union/inline/error-set registration class). Regression
test: examples/0417-protocols-protocol-return-name-collision.sx.
- 0132: rewrite to the verified root cause -- protocol method signature
registration resolves type names via flat findByName and picks the wrong
same-name author. Original payload-field hypothesis kept as superseded;
repro switched to canonical `impl ... for` syntax. Still open (the
protocol path is unchanged).
- 0133: assigning a struct literal to a union member panics ("unresolved
type reached LLVM emission"); pre-existing, surfaced while testing.
- 0134: a same-name `error` set collapses into a namespaced import's set --
error-set declarations lack per-decl nominal identity (E6a gap); this is
what keeps the 0132-class error-ref resolution dormant.
Enum payloads, union fields, inline struct/enum/union field types, and
named error-set references now resolve through the visibility-aware
`inner` recursion hook (the same seam `resolveCompound` uses) instead of
the flat `findByName`. A bare type name in any of these positions now
selects the querying module's OWN author over a same-name namespaced
import -- the own-wins rule already applied to top-level named references
and struct fields.
- buildEnumInfo / buildUnionInfo / resolveInlineEnum / resolveInlineStruct
/ resolveInlineUnion / resolveErrorType take the `inner: anytype` seam;
registerEnumDecl / registerUnionDecl and the struct-const annotation
pass `self` (visibility-aware); resolveAstType passes the stateless `si`.
- resolveTypeWithBindings routes inline type decls and named error refs
through `self` instead of delegating to flat resolveAstType.
Regression tests: examples/0781 (top-level enum payload over a namespaced
import), examples/0784 (inline struct field). Addresses issue 0132's
broader latent class; the protocol-return case (0132 primary) is a
separate registerProtocolDecl fix and stays open. The error-set reference
path is in place but dormant pending error-set per-decl nominal identity
(issue 0134).
`zig build test` now runs the full examples/ + issues/ regression corpus
alongside the Zig unit tests, driven by a pure-Zig test
(src/corpus_run.test.zig) — no shell script in the build path. It spawns
the installed `sx` per example (subprocess-isolated, per-run timeout),
diffs stdout/stderr/exit and optional `sx ir` snapshots, and fails the
build on any mismatch. The file list is enumerated at runtime, so new
examples are covered with no test edit.
- `sx ir` / `ir-dump` now write to stdout (fd 1) instead of stderr, so
the dumps can be piped/redirected.
- `zig build test -Dupdate-goldens` regenerates snapshots in-build,
byte-identical to the legacy `run_examples.sh --update`; on mismatch
the runner prints how to regenerate.
- run_examples.sh kept (still used by tools/verify-step.sh) and made
portable to a bare macOS: timeout/gtimeout fallback, bash 3.2-safe
empty-array handling.
- CLAUDE.md: document the new workflow.
THREADSAFE=0 was correct when sx had no threads; with std.thread (S6)
and std.http's pooled dispatch (S7b), concurrent connections corrupted
sqlite's unprotected globals (caught live: distd under ab -c20 died
with free-of-unallocated inside yy_reduce). Serialized mode is
sqlite's own default and safe for every consumer; per-connection use
across threads is the supported pattern.
thread_pool_count = 0 (default) keeps handlers inline on the loop
thread — the measured fast path (BENCH-HTTPZ.md). N > 0 dispatches
each parsed request to a std.thread Pool of N workers, completing the
httpz two-pool shape: the connection freezes as CONN_HANDLING (no
reads, growth, eviction, or recycling — the worker borrows views into
its read buffer), the worker runs the handler under a per-job arena
and serializes into job-owned bytes, the completion queues under the
PoolState mutex, and the loop wakes through the new std.event wake
channel (kqueue EVFILT_USER + EV_CLEAR; the epoll twin maps to
eventfd), attaches the response, compacts the buffer, and resumes
keep-alive/pipeline handling. A full backlog sheds with 503. Stale
completions (generation mismatch after close) are dropped. Pool mode
requires the server's constructing allocator to be thread-safe
(GPA/malloc), documented on the knob.
PoolState lives behind a heap pointer (it embeds a Mutex and is shared
with workers; the Server struct itself is returned by value).
serialize_response/run_handler_job share one serialize_bytes.
examples/1633 gains the pooled section (GET, body echo, 404 across
worker threads) plus the loop-wake path exercised end to end; AOT run
five times. examples/1632 unchanged but the Event struct gains `user`.
pthread bindings with darwin opaque sizes (mutex 64B, cond 48B; glibc
divergence is a C3 per-OS item). Mutex/Cond initialize IN PLACE and
Pool lives behind Pool.create's heap pointer — POSIX sync objects are
address-sensitive, so nothing here moves after setup. Thread.spawn
takes the C2 re-entry contract entry (callconv(.c), fabricates its own
Context); Pool workers do exactly that with a per-worker malloc-backed
GPA, then run default-conv tasks inside it. submit returns false on a
full backlog (httpz thread_pool backpressure); shutdown finishes
queued work and joins every worker.
examples/1637 pins: 4 raw threads x 1000 locked increments, 100 pool
tasks summing exactly once across 4 workers, a held worker + full
backlog refusing the next submit, clean shutdown. JIT + AOT (AOT run
three times). The std.sx barrel carries thread; .ir snapshot regen is
the usual renumbering.
Both halves of the C2 contract already work in JIT and AOT; these
examples pin them. 1635: libc qsort drives an sx callconv(.c)
comparator passed by name as a typed fn-pointer param. 1636: a real
pthread enters sx through a callconv(.c) entry, fabricates its own
Context (push Context with a local GPA), and runs default-conv sx code
that allocates through it — the re-entry contract std.thread (S6)
stands on. Also unblocks the sqlite callback APIs (hooks/UDFs) left
unbound by design in P5.1.
emitProtocolDispatch now requires the user-arg count to equal the
protocol method's parameter list — exact, since protocol signatures
have no defaults, packs, or variadics — and emits the same
"expects N arguments, but M were given" diagnostic plain calls get.
Previously extra args were silently dropped (and missing args left the
thunk reading garbage). The dispatch gains the call-site span for the
diagnostic. examples/1634 pins the rejection; full sweep confirms no
existing code relied on the leniency.
The protocol declares dealloc_bytes(ptr) — the size argument I passed
at three sites was silently accepted and dropped by the compiler
(issue 0131); these calls would stop compiling the moment that
diagnostic gap is fixed.
No conjured GPA: the arena chunks come from own_alloc (captured at
Server.init), so all server memory flows from the allocator the app
constructed it with — the point of the implicit context model.
Handler and serialization allocations through the implicit context die
with the request; response bytes survive via the own_alloc copy made
inside the push scope. Without this every request leaked its render
concats into the loop's long-lived context.
read_buf_cap is now the per-request LIMIT, not a preallocation: slots
start at 16K, double when full (one-step sizing when a Content-Length
declares the body), and keep their grown capacity for slot reuse. At
the limit the refusal distinguishes oversized headers (431) from an
oversized body (413). Unblocks A1: distd accepts multi-hundred-MB
artifact uploads — preallocating that per slot was never an option.
examples/1633 adds a body past the initial capacity echoing intact.
Server.init(cfg, handler, ctx); the handler signature gains a usize
third argument delivered verbatim per dispatch — typically a pointer
to the app's own state, since the server owns the call site. A bare
(req, resp) handler had no way to reach app state without globals.
examples/1633 pins the round trip.
The httpz shape, one worker, handlers inline over the std.event Loop:
nonblocking accept, per-connection state machine (reading -> writing ->
keepalive/close) with incremental parsing (request line, headers,
Content-Length body), partial-write continuation via on-demand write
interest, pipelined-request draining, and timeouts as EVICTION —
request-delivery and keepalive-idle deadlines on the monotonic clock,
checked after I/O each tick. Keep-alive is the HTTP/1.1 default;
Connection header, HTTP/1.0, or the per-connection request_count cap
turn it off. Config mirrors httpz: port/backlog/max_conn/read_buf_cap/
timeout_request_ms/timeout_keepalive_ms/request_count.
API: Server.init(cfg, handler) + tick(max_wait_ms); run() is the
forever-tick loop. tick makes the server drivable single-threaded —
examples/1633 runs a live server and its client sockets in ONE thread,
pinning: GET with keep-alive, actual connection reuse, the request cap
answering Connection: close then EOF, POST body echo, 404 routing, and
a half-header client evicted at the request deadline while a healthy
client keeps being served. Verified under sx run AND sx build.
Connection slots and read buffers are reused across connections
(httpz's min_conn/buffer-pool spirit); response buffers are allocated
per response and freed on completion. Serialization happens while
request views are valid, the served bytes are compacted, and only then
does sending start — write_more's pipelining check must see only the
remainder. The std.sx barrel carries http; .ir snapshot regen is the
usual mechanical renumbering.
S7b adds worker counts + the handler thread pool (needs C2/S6); the
epoll backend activates with the linux target (S4/S7c).
Loop.init/close, add_read/del_read/add_write/del_write with a
per-registration udata word, and wait() normalizing backend events
into Event{fd, udata, readable, writable, eof, err, nbytes}. The epoll
twin (S4) slots in behind this surface when the linux target lands.
No timer registrations by design: request/keepalive eviction is
deadline math — deadline_in/expired/remaining_ms over std.time's
monotonic clock, with remaining_ms feeding wait's timeout. std.sx
barrel carries ; .ir snapshot regen is the usual mechanical
renumbering. examples/1632 pins idle timeout (and that it honors the
deadline), readable with fd/udata/nbytes, immediate writability on an
empty send buffer, and the eof flag on peer close; JIT + AOT.
32-byte darwin struct kevent, EVFILT_READ/WRITE/TIMER, EV_* flags, and
three thin helpers: kev_change (one registration entry), kq_apply
(immediate change, no drain), kq_wait (bounded drain, EINTR reissued,
negative timeout = forever). Off the std.sx barrel by design — the
OS-neutral facade over this and the epoll twin is std.event (S5).
examples/1631 pins zero-cost idle timeout, READ readiness with pending
byte count + udata round-trip, and EV_EOF on peer close; verified under
sx run AND sx build.
set_nonblocking (C-variadic fcntl), errno via __error (darwin; C3
selects per-OS), and accept_nb/read_nb/write_nb returning a typed
SockErr — WouldBlock / Closed / Fault — so readiness-loop callers never
parse -1/errno pairs. EINTR retries internally; accept_nb skips
ECONNABORTED. Adds connect, shutdown, socketpair, AF_UNIX, SHUT_*.
examples/1630 pins the result algebra on a socketpair and a nonblocking
TCP listener (WouldBlock on empty backlog, accept after loopback
connect); verified under sx run AND sx build. The .ir snapshot regen is
mechanical: new std decls shift @str/@tag.str numbering and grow the
type table (179 -> 185).
now_secs (CLOCK_REALTIME, epoch seconds) and mono_ms (CLOCK_MONOTONIC,
process-local milliseconds for deadlines). Clock ids are darwin's; the
per-OS selection mechanism is PLAN-HTTPZ C3. No error channel: with
module-constant clock ids and a stack timespec, clock_gettime is total.
std.sx namespace tail carries the time alias; examples/1629 pins epoch
plausibility, monotone advance, and the alias carry.
The JIT path already guards its object cache with hasTopLevelRun (the
#run interp executes during codegen; a cache hit skips codegen and
loses its effects). The build path had no such guard, so a second
'sx build --cache' of any app with a '#run configure_build()' block
linked WITHOUT the build.sx config — no link flags (m3te: undefined
SDL3 symbols), and on a binary-level hit the output path and bundling
would have been wrong too. Both cache levels and both save sites now
share the guard; #run-free programs keep full cache behavior
(verified: second build hits the binary cache in <1ms; m3te's
build/--cache/build sequence now links and bundles both times).
All units share one link namespace (per-unit isolation is PLAN-C C3.2,
deferred), so a symbol defined by two units previously died inside the
JIT dylib link or the AOT link with raw linker spew. The clang shim
gains sx_clang_object_exported_symbols (llvm::object scan: defined +
global, format-specific excluded) and compileCToObjects cross-checks
every unit object — collisions name both source files. Scan failures
are non-fatal; the linker remains the backstop. Covers JIT and native
AOT; the emcc path still relies on wasm-ld's own error.
compileCWithEmcc now probes/saves .sx-cache/c-<key>.o with the same
content key as the native path (source + declared headers + transitive
deps + defines/flags/incdirs), keyed by the emcc --version line and the
wasm triple so emsdk upgrades and wasm32/64 variants never collide with
each other or with native objects. Cache hits hand the linker the cache
path directly. objectMagicOk accepts the wasm magic. Verified: warm
wasm build of a c-unit drops 1.85s -> 0.61s (emcc -c skipped).
The key previously covered the #source bytes + the block's DECLARED
headers, so a unit whose impl is a thin wrapper over an undeclared
header (vendors/kb_text_shape: two-line impl.c, all code in
kb/kb_text_shape.h) would serve STALE cached objects after an
upstream upgrade. collectIncludeDepBytes now walks the transitive
closure of quoted #include lines (includer-dir first, then -I dirs;
angle/system includes never participate; unresolvable names skip) and
the dep contents fold into the key — no sidecar, no compare logic, a
changed header is just a different key. Verified live: appending to
kb_text_shape.h mints a new cache entry; reverting hits the old one.
kb_text_shape (v2.10, JimmyLefevre) had been LOST from the sx tree —
ffi/stb_truetype.sx referenced repo paths that no longer existed (and
nothing runs glyph_cache, so the dangling unit never fired). The
trimmed copy returns from the m3te project as a proper vendor:
curated c/kbts_api.h decls over the full upstream header, README with
provenance, and examples/1627 pinning context + font creation so the
unit compiles and runs in-suite. file_utils (in-house asset-read
helper with the Android AAssetManager hook) gets the same unit shape.
modules/ffi/stb_truetype.sx is gone: glyph_cache imports the three
vendored units (stb_truetype, kb_text_shape, file_utils) directly.
The stb headers move from the repo-root vendors/ (resolvable only
with CWD = sx repo) into library/vendors/ following the sqlite
convention — bindings module + c/ sources + provenance README — so
'#import "vendors/stb_image/stb_image.sx"' (image v2.30 + image_write
v1.16) and '#import "vendors/stb_truetype/stb_truetype.sx"' (v1.26)
work from any consumer via the stdlib search paths. modules/ffi/stb.sx
dissolves into the stb_image vendor; modules/ffi/stb_truetype.sx keeps
its non-stb text-shaping companions and re-imports the vendored unit.
examples/1625 pins a deterministic in-memory BMP decode; examples/1626
pins font init + metric invariants against the system Helvetica.
The vendored amalgamation (3.53.2, public domain) plus the curated
bindings move from the distribution repo into the sx library:
'#import "vendors/sqlite/sqlite.sx"' gives any sx program SQLite
with no system dependency and no build flags — the bindings declare
the C as a named #import c unit (pinned defines + -O2), compiled
through the object cache and shadow-proof via unit-first resolution.
examples/1624 pins the version and a typed round trip in-suite.
One module imported through several aliased chains materializes one
c_import_decl copy per chain, each carrying a differently-spelled
relative path to the same file (src/app/../repo/../db/../../vendor/x.c
vs src/db/../../vendor/x.c). Dedup now keys on lexically-normalized
sources/includes + defines + flags, so the unit compiles and links
exactly once — pointer-identity dedup linked it once per chain and
died with duplicate symbols at AOT link.
A named #import c unit declared inside an aliased module sits two
namespace levels deep in the merged tree; the one-level walk (the
extractLibraries/0130 pattern in c_import form) never collected it,
so the unit silently never compiled and its symbols resolved from
whatever process image carried the same names — surfaced by C4's
sqlite migration, where only the version pin could tell the OS copy
from the vendored one.
validateForeignRefs walks the merged tree (libraries + named c units,
nested namespaces included) and diagnoses any #foreign whose ref names
neither — a typo'd ref previously compiled and resolved silently
through whatever image carried the symbol. Decls synthesized from
#include headers carry no ref and are exempt. Flips the C0.2b pin;
zero collateral across the 608 other examples.
runJITFromObject now takes priority dylibs (the #import c unit's
linked objects first, then #library deps in declaration order) and
attaches a per-path search generator for each AHEAD of the
process-wide fallback, so a vendored symbol can never lose to a
same-named export of an image the host process happens to carry
(libz via LLVM, libsqlite3 via CoreServices). loadLibrary reports
the name dlopen succeeded on; the c-import handle records its dylib
path; temp link inputs are per-pid so concurrent runs can't clobber
each other. Flips the C0.3 shadowing pin to from_unit: true.
compileCToObjects now probes .sx-cache/c-<key>.o before invoking the
embedded clang and writes fresh objects back (per-pid temp + copy, the
main object cache's pattern). Default on for both JIT and AOT — the
temp-compile-and-delete behavior it replaces was strictly worse. A
cached entry must carry an object-file magic (Mach-O/ELF) or it falls
back to a fresh compile; no cache failure can fail a build. Cold/warm
verified via --time: the object compile disappears on the warm run.
Source bytes, declared-header CONTENT (header edits invalidate),
defines/flags/include dirs in order, LLVM version, and target
triple/sysroot all participate; section tags keep equal strings in
different roles distinct. Pure function + variance property tests;
nothing consumes it yet.
extractLibraries/extractFrameworks walked the merged root plus exactly
one namespace_decl level, so a #library reached through two or more
aliased imports never made it to the AOT link line or the JIT dlopen
list. Both walks now recurse over namespace_decl children.
Regression: examples/1617-modules-library-nested-namespace.sx binds
libpcap (not in the compiler's loaded images, so the JIT cannot mask
the miss via RTLD_DEFAULT) behind two aliased imports.
cstring is ONE pointer to a null-terminated u8 buffer, C's char*: thin
(8 bytes, no length; cstring_len walks to the terminator), crossing
#foreign boundaries verbatim in both directions, with ?cstring as the
nullable case lowering to the same bare pointer (null = absent).
Conversion discipline mirrors Odin: a string LITERAL coerces implicitly
(its bytes are terminated constants); any other string is rejected with
a diagnostic naming to_cstring (it may be an unterminated view); and
cstring never coerces to string implicitly — from_cstring(c) is the
explicit zero-copy view, pricing the strlen.
Plumbing: TypeId/TypeInfo builtin slot 18 (first_user 19), name
classifiers, size/align/name tables, LLVM ptr lowering, the ?T pointer
niche, the xx pointer ladder, the literal-gated coercion plan
(isConstString + data_ptr), and the reserved-spelling set. std gains
cstring_len/from_cstring/to_cstring (fmt.sx, re-exported); the old
cstring(size) allocator helper is renamed alloc_string everywhere;
getenv migrates to (name: cstring) -> ?cstring as the canonical user
and env() drops its manual strlen/memcpy.
Pinned: examples/1222 (FFI both directions, literal coercion,
?cstring null paths, round trip) and examples/1173 (both coercion
diagnostics); FAIL pre-feature. The alloc_string rename + getenv
signature shift the .ir snapshots — regenerated. zig build test
426/426; run_examples 604/604.
Spec: reserved spelling + cstring section + C-interop rows.
Two genuine defects behind the 0128 filing (whose original repros were
both poisoned by binding getenv, which std already declares -> *u8):
1. Re-declaring a C symbol was silent first-wins: every call through
the later declaration was typed by the older signature. Foreign
registration now dedupes — equal signatures share one FuncId,
conflicting ones are diagnosed.
2. Foreign -> string / -> ?string returns read garbage: C returns one
char*, but the LLVM signature declared the fat {ptr,i64} (len =
register garbage), and ?string was mis-declared SRET (the hidden
out-pointer landed in the callee's first arg register). cstrRetKind
now classifies such returns, declares them as plain ptr (never
sret), and the call site synthesizes {ptr, strlen} via a
branch-guarded strlen (NULL -> {null,0} / optional null), wrapping
{string, i1} for ?string.
?[:0]u8 itself resolves fine (it is ?string); the spelling works in
return, param, local, and alias positions.
Regression: examples/1221 (plain + optional non-null + NULL paths) and
examples/1172 (conflict diagnostic); both FAIL pre-fix. The extern
dedupe collapses duplicate libc decls, so affected .ir snapshots were
regenerated. zig build test 426/426; run_examples 602/602;
distribution suite 21/21.
