The hosted loop's scheduling entries (a tick, a timer or an immediate goes
through the bootstrap's helpers; a checkpoint drains ticks and microtasks)
and island process-event listeners called the bridge on whatever stack the
runtime was on: the main thread's for the first checkpoint, or an async
fiber's. JavaScript then ran there, and a collection it triggered failed
V8's "Check failed: isolate_->IsOnCentralStack()" (node-island-handles,
about 1 run in 15 sanitized: promise reactions run by the first checkpoint
on the main stack allocated a microtask). They now run on Node's stack like
every other entry, below the mark when they come from a fiber.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
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>
g01 (twenty fs.stat round trips against a 2 ms timer), p10 (two 0 ms
timers armed on either side of an island call) and s06 (fs callbacks and
timers pending when Node loads) each failed one CI run in a different
lane: their order depends on how long the island call or the I/O takes,
which differs between the sides and grows under ASan. Their native runs
now have to produce the lines of one of Node's outputs, like the other
race programs.
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>
The sanitized seed compiles the compiler's 700 MB LLVM module with one clang
process under AddressSanitizer. The compile peaks near 14 GB while the Node
process that emitted the module still holds about 6 GB, which exceeds the
runner's 16 GB of memory. The job now enlarges swap to 24 GB before it builds
the seed, as the sanitized emitter job does.
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.
Malte Ubl