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When Emscripten's WASM memory grows (due to -sALLOW_MEMORY_GROWTH), all existing TypedArray views become detached because the underlying ArrayBuffer is replaced. This caused bugs where reading from views after FFI calls returned undefined values if memory had grown. The fix introduces RefreshableTypedArray, a wrapper that lazily recreates the TypedArray view when HEAPU8.buffer changes. This is a simple reference comparison that only triggers view recreation when actually needed. Affected call sites: - runtime.ts: executePendingJobs - reads ctxPtrOut after QTS_ExecutePendingJob - context.ts: newPromise - reads resolve/reject handles after QTS_NewPromiseCapability - context.ts: getLength - reads uint32Out after QTS_GetLength - context.ts: getOwnPropertyNames - reads outPtr and uint32Out after QTS_GetOwnPropertyNames Also fixed: getOwnPropertyNames was using HEAP8.buffer instead of HEAPU8.buffer Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
- getArrayBuffer returned a HEAPU8.subarray view that is detached by the next WASM memory growth; return a copy instead. - consumeJSCharPointer / consumeHeapCharPointer leaked the C string when UTF8ToString threw (e.g. strings longer than V8's max string length). - newArrayBuffer leaked the host buffer (and returned an exception-tagged handle) when QuickJS failed to create the ArrayBuffer. It now frees the buffer and throws. Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
…reelist - ModuleMemory helpers now throw on a null _malloc instead of writing at address 0. - getOwnPropertyNames freed a plain-malloc'd array with js_free (QTS_FreeVoidPointer), unbalancing QuickJS allocation counters; free it with the module's free. - HostRefMap: FIFO freelist used Array#shift (quadratic when draining); use a head index. Deleting an already-deleted id in a non-empty group no longer queues it for reuse twice. Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
…y arguments - QTS_RuntimeDumpMemoryUsage wrote into a fixed 1 KiB fmemopen buffer, truncating the report mid-line once more than a few object kinds exist. Use open_memstream. - QTS_Call built a variable-length array of argc values on the wasm shadow stack; a few hundred thousand arguments trapped the whole module. Heap allocate instead, and throw out-of-memory if that fails. Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
…wnPropertyNames - newContext (sync and asyncify) wrapped a NULL context pointer and carried on; throw. - ContextMemory.heapValueHandle wrapped the NULL returned by jsvalue_to_heap when it cannot malloc; throw. - QTS_GetOwnPropertyNames did not check its output malloc, and sized it per JSValue (8 bytes) instead of per JSValue* (4 bytes); check it, free the property atoms and throw out-of-memory on failure. Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
This was referenced Oct 16, 2026
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Layer: C interface + TypeScript wrapper
Review just this PR: jackkav/quickjs-emscripten@fix-c-dump-and-call-args...fix-c-null-checks
Stack: #248 → #276 → #277 → (#278 | #279 → #280 → #281 → #282). Issues: #274, #275.
What
newContext()(sync and asyncify) throws if QuickJS returns a NULL context instead of wrapping pointer 0.heapValueHandlethrows on the NULL thatjsvalue_to_heapreturns whenmallocfails.QTS_GetOwnPropertyNames: check the outputmalloc, size it perJSValue*(was perJSValue, 2x too big), nevermalloc(0); on failure free the atoms and return an OOM exception.Test:
newContextunder a 1-byte limit andheapValueHandle(0)fail without the change. Gap: the NULL branch insideQTS_GetOwnPropertyNamesisn't tested (can't make a plainmallocfail on demand); an empty-object test guards themalloc(0)edge.Verified on: Full suite on freshly built wasm for every variant in the test matrix (sync/async × release/debug × quickjs/quickjs-ng) at the top of the stack (#282): 751 passed, 0 failed. Debug builds run the leak sanitizer check in
afterAll.Behavior change:
newContext()under memory exhaustion throwsFailed to create QuickJSContext (out of memory)instead of returning a broken context.Overlap: #207 also edits
c/interface.candruntime.ts; no conflicting intent, possible textual conflicts.🤖 Generated with Claude Code