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Chris Tate
8eb5ad28e5
Externrefs a guest holds are borrowed pointers. An import's result was
kept only until the outermost call returned, which was before the export
call converted its results to JavaScript, so a result created by an
import was freed before conversion. A table or global slot released the
reference it replaced at once, although the guest may still hold it in a
local after reading the slot. The kept references are now released after
the outermost caller has converted its results (scr_wasm_leave), and a
table or global store during a call keeps the reference it replaces until
then.
Checked memories (explicit bounds checks: sanitized builds, Windows)
grew with realloc, which can move the storage that memory.buffer and its
views alias. They now reserve the address space for their largest size
(mmap on POSIX hosts, VirtualAlloc on Windows) and commit pages as they
grow, so the base never moves. Hosts without address-space reservation
grow in place only until a buffer has been handed out; after that,
growth that would move the storage fails.
Tests: webassembly-externref-lifetimes.mjs (import results through an
export, table and global references replaced by the guest and by
JavaScript), webassembly-memory-growth.test.ts (views written after
growth from JavaScript and from the guest), and translate.test.ts cases
for memargs naming memory 0 explicitly and for local.tee operand types,
which b3bcbaaf7 made consistent with validation. Under SCRIPTC_SAN=1 the
two runtime tests report heap-use-after-free without these changes.
Merges main; internal/compatibility/generated/node-v24-backlog.json is
regenerated with pnpm node-compat.