Calls into Node now run on one dedicated 64 MB stack with a guard page,
reached by a context switch, and the bridge sets V8's stack limit on it
(bridge ABI 2). Before, a call from an async fiber (512 KB stacks without a
guard page) failed to bootstrap Node, which the dev-mode LLVM differential
showed. The runtime's stack guard follows the switch, and the switch
carries ASan's fiber annotations.
The Node island tests load Node from a libnode pack. Until the NI-13 packs
are published, .github/actions/libnode-dev-pack assembles one for the
Linux x64 test lanes (plain and sanitized): a pinned, checksum-verified
prebuilt libnode of the repository's Node release (24.22.0) and Node's
official headers (packages/libnode-common/dev-pack.json), with the bridge
built against them by build-pack.mjs. The pack is cached by its inputs and
the bridge source, so only a cache miss downloads and builds; the normal
build path never does.
tests/harness/libnode.ts makes a missing pack a failure in those lanes:
island tests skip only off Linux x64 CI without a configured pack. The
bridge smoke test (packages/libnode-common/test/bridge-smoke.c) loads the
pack the way scr_node_island.c does and makes synchronous, throwing and
asynchronous calls through the bridge with the runtime's bootstrap.
IR, LLVM and object outputs of programs that call into Node no longer need
a pack at build time; only executables record one.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Scope-B milestone NI-1, runtime side. Programs whose IR has a
`nodeIsland.*` operation link scr_node_island.c and the SCR_NODE_ISLANDS
build of scr_async.c; every other program links neither, byte for byte.
- scr_node_island.c dlopens the bridge of a libnode pack on the first call
(RTLD_NOW | RTLD_GLOBAL), checks its bridge ABI and that it links exactly
the Node version recorded at build time, starts one Node environment and
runs the embedded bootstrap (scr_node_island_host.cjs). A run that never
calls into Node never maps libnode. The pack directory is SCRIPTC_LIBNODE
at run time, else the recorded path; a `$ORIGIN/` path resolves against
the executable's directory (the beside packaging, and the hook for
shipping Node with the program).
- scr_node_bridge.h is the C ABI between the runtime and the bridge; the
runtime includes no Node or V8 header. The bridge
(packages/libnode-common/bridge/scr_node_bridge.cc) initializes Node once
with no default signal handling, no debug-signal handler or inspector,
no stdio reinitialization and one platform worker, creates the
environment from the built-in snapshot, routes Node's process exit to
the runtime's exit sequence, promotes libnode to the global scope for
native addons, and runs calls in a CallbackScope with a TryCatch.
build-pack.mjs assembles a pack (libnode, the bridge, manifest.json) from
a Node --shared build and the matching headers.
- The SCR_NODE_ISLANDS build of scr_async.c adds a loop slot through which
the runtime's loop drives Node's until NI-3 hosts the runtime's queues on
Node's libuv: it keeps the program alive while Node has ref'd work,
sleeps on Node's backend fd up to its next timer, and runs one
non-blocking turn per loop turn.
- The `nodeIsland` runtime feature (rule, link features, unit table, pack
matrix row and scr_async.c variant), the nodeIsland.call/callSync
libCalls, the install call in main, and the build-time record of the
pack (node-islands/libnode.ts: --libnode=<pack>|beside or
SCRIPTC_LIBNODE, SC8005 when none is usable, Node >=24.13.1).
- The zero-cost gate and the bench nm test require that no good-code
executable defines a Node island symbol.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
