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Author: juj

system/include/emscripten/wasm_worker.h

@@ -188,6 +188,10 @@ void emscripten_lock_busyspin_waitinf_acquire(emscripten_lock_t *lock __attribut
 // NOTE: This function can be called in both main thread and in Workers. If you
 //       use this API in Worker, you cannot utilise an infinite loop programming
 //       model.
+// NOTE 2: This function will always acquire the lock asynchronously. That is,
+//         the lock will only be attempted to acquire after current control flow
+//         yields back to the browser, so that the Wasm call stack is empty.
+//         This is to guarantee an uniform control flow.
 void emscripten_lock_async_acquire(emscripten_lock_t *lock __attribute__((nonnull)),
                                    emscripten_async_wait_volatile_callback_t asyncWaitFinished __attribute__((nonnull)),
                                    void *userData,