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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>
This was referenced Oct 16, 2026
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Layer: TypeScript wrapper
Review just this PR: jackkav/quickjs-emscripten@fix-memory-growth-views...fix-views-and-leaks
Stack: #248 → #276 → #277 → (#278 | #279 → #280 → #281 → #282). Issues: #274, #275.
What
getArrayBufferreturned aHEAPU8.subarrayview that heap growth detaches (same class as Fix WASM memory view invalidation when memory grows #248). Now returns a copy.consume*CharPointer: free the C string even ifUTF8ToStringthrows.newArrayBuffer: free the host buffer if QuickJS fails to create the ArrayBuffer (it only takes ownership on success).Test: 3 new tests + 5 for #248 itself; each fails without its fix. Leak tests spy on
_malloc/_free, and every test'safterEachdisposal runs the runtime's no-leak assertion (and the sanitizer check on debug builds).Verified on: All variants in the test matrix, TS-only so published 0.32.0 wasm is representative; the same tests also pass on freshly built wasm at the top of the stack (751 passed, 0 failed).
Behavior change:
getArrayBufferresult is a copy (dispose()is a no-op).newArrayBufferthrows the QuickJS error instead of returning an exception-tagged handle.Overlap: Builds on #248 (includes its commits rebased on
main, plus regression tests for it). #207 does not touch these code paths.🤖 Generated with Claude Code