structuredClone in an island of a value holding native records, class
instances or objects (interceptor objects V8's serializer cannot clone)
clones a plain copy of that data, as Node clones the objects themselves.
An island array of primitives or strings (or arrays of those) returned
directly or through a promise crosses as a copy, which the checked cast
then meets, instead of failing the cast as an object handle.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
A plain object a program passes into an island is an object-template
instance, which inherits from its implicit constructor's prototype object;
island code that checks for plain objects (jose's isObject:
Object.getPrototypeOf(o) === Object.prototype) rejected it. The instance now
inherits Object.prototype directly. Corpus 6826 checks it.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
A call into Node from an async fiber runs in a context of its own on Node's
stack while the calling fiber stays suspended in it, but runtime code that
Node called back there still ran as that fiber: scr_current named it, and
a fiber resumed from there saved its resumer in scr_loop_ctx and, under
ASan, its fake stack in the calling fiber's slot. The calling fiber's next
park then returned to a context that no longer existed, or under ASan
resumed with a fake stack the nested context had destroyed
(6870-node-island-server-fibers in dev mode, sanitized: SEGV in
nh_keep_done). The nested entry now runs host callbacks as the loop's code
does (no current fiber, the main exception cell and ALS slot) and puts the
calling fiber's state and the loop context back when it returns.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
A gap fence inside a function body may never run, so it no longer makes its
package a Node island under --node-islands=auto: only fences in top-level
module code and fences that need the JavaScript runtime do. The package's
island class still decides after a failed build. Typed packages like jose
stay native (DECISIONS.md, 2026-10-21), so the corpus pins of jose and
run-node are gone.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
CI's island lanes fall back to the development pack (dev-pack.json: Node
24.22.1, no package.json) until the libnode-packs cache exists, so the
smoke test, which verifies a @scriptc/libnode-<platform> package against
the 24.22.0 pin, failed there. It now runs only when SCRIPTC_LIBNODE names
a package directory. The pack package versions follow the 0.4.2 release
(scripts/sync-versions.mjs), which pin.test.ts checks.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Release builds no longer import runtime bitcode, so program code called scr_map_retain_v for every Map read out of a container and scr_map_size for every size read. A Map retain now uses the emitted increment helper, as string retains do, and Map.size reads the live count through an internal helper.
A number parameter that every call site proves an int32 reaches the
function's i32 entry. One that some caller passes as an unproven number,
such as a value read from a worker message or parsed from text, kept its
double, so every loop it bounds compared an integer counter with a double
limit and the values derived from it stayed doubles.
When such a parameter bounds a numeric loop (arithmetic, element and
field reads and writes, Math calls, no allocation or other calls), the
function now gets a copy of its body. Its own body first tests
each such parameter for an int32 that is not -0 and, when all pass, calls
the copy with `p | 0`, the same double. The copy's only caller proves
those parameters int32s, so it gets the i32 entry and integer loops.
Other values run the body as before.
Only plain synchronous functions of at most 2048 IR nodes are versioned:
not class members or generated helpers, not capturing, not the entry,
not dynamic-tier, not calling themselves, and at most 16 per module. A
function holding the only call site of another function is kept whole
unless that callee only computes a number or boolean from scalar reads:
a second call site can stop LLVM from inlining the callee and leave the
records it builds in memory. Library builds and modules that observe
call stacks are left as they are.
tsgo has no getContextualTypes or getResolvedSignatures. Each prefetch
asked for them anyway, and a failed chunk was split and retried down to
single nodes, so a tsgo build paid about two failed requests per
prefetched node. The checker facade now remembers a batch method the
server answers with "unknown API method" and asks those queries node by
node from then on.
A typed record encoded from its field hooks queued a plain-object field on
the visit stack and went on to the next field, so getters on later fields
ran before the properties of earlier ones were read. Node's serializer
finishes each field, nested properties included, before the next.
The record path now drains the visit stack down to where it started after
each field, so properties are read in Node's order. Corpus 7139 posts a
record whose fields hold getter-bearing objects and prints the read order.
A function expression stored in a function type with more parameters
folds `arguments.length` to that type's parameter count, the count every
call through the slot passes. A named expression that calls itself
through its own name passes only its declared parameters there, so no
constant answers both calls. Such a read now reports SC1090 with the
reason, and expressions that do not refer to their own name keep the
fold.
The trip count that bounds a follower's range was the driver's span over
its step, computed in doubles. A span above 2^53 - 1 can round down: from
-(2^53 - 1) to below 2^52 - 1 the span 3 * 2^52 - 3 becomes 3 * 2^52 - 4,
so a follower that reaches 2^53 got the range limit 2^53 - 1 and ran as an
unchecked integer. Such a span now bounds no trip count, and the follower
is tested at run time (or the loop is refused when every value is known).
Below it the quotient rounds to at least its floor, and the follower's
products and sums are exact within the safe range.
Malte Ubl