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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>
This was referenced Oct 16, 2026
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Layer: C interface (
c/interface.c)Review just this PR: jackkav/quickjs-emscripten@fix-oom-and-hostref...fix-c-dump-and-call-args
Stack: #248 → #276 → #277 → (#278 | #279 → #280 → #281 → #282). Issues: #274, #275.
What
QTS_RuntimeDumpMemoryUsageused a fixed 1 KiBfmemopenbuffer, cutting the report mid-line. Nowopen_memstream.QTS_Callbuilt a variable-length array ofargcvalues on the wasm stack; ~700k+ args trapped the whole module. Now heap-allocated, withJS_ThrowOutOfMemoryon failure.Test: 2 new tests, both fail on wasm built from
main(truncated report;memory access out of bounds) and pass with the change. The call-args test also checks the module still evaluates code afterwards.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:
callFunctionwith a huge argument list returns a catchableInternalErrorinstead of killing the module.Overlap: #207 also edits
c/interface.c(memory-usage code); possible textual conflict nearQTS_RuntimeDumpMemoryUsage, no conflicting intent.🤖 Generated with Claude Code